Oracle® OLAP Java API Developer's Guide 11g Release 2 (11.2) Part Number E10795-06 |
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This chapter describes Source
objects, which you use to specify a query. With a Source
, you specify the data that you want to retrieve from the data store and the analytical or other operations that you want to perform on the data. Chapter 6, "Making Queries Using Source Methods", provides examples of using Source
objects. Chapter 10, "Creating Dynamic Queries", describes using Template
objects to make modifiable queries.
This chapter includes the following topics:
You use Source
objects to create a query that specifies the data that you want to retrieve from the database. As a query, a Source
is similar to a SQL SELECT
statement.
To create a query, you typically use the classes in the oracle.olapi.metadata.mdm
package to get MdmSource
objects that represent OLAP metadata objects. From an MdmSource
object, you can get a Source
object. You can also create other kinds of Source
objects with methods of a DataProvider
. You can then use these Source
objects to create a query. To retrieve the data specified by the query, you create a Cursor
for the Source
.
With the methods of a Source
, you can specify selections of dimension members, attribute values, or measure values. You can also specify operations on the elements of the Source
, such as mathematical calculations, comparisons, and ordering, adding, or removing elements of a query.
The Source
class has a few basic methods and many shortcut methods that use one or more of the basic methods. The most complex basic methods are the join(Source joined, Source comparison, int comparisonRule, boolean visible)
method and the recursiveJoin(Source joined, Source compariso4n, Source parent, int comparisonRule, boolean parentsFirst, boolean parentsRestrictedToBase, int maxIterations, boolean visible)
method. The many other signatures of the join
and recursiveJoin
methods are shortcuts for certain operations of the basic methods.
In this chapter, the information about the join
method applies equally to the recursiveJoin
method, except where otherwise noted. With the join
method you can relate the elements of one Source
to those of another Source
by joining a Source
with an input to a Source
that matches with that input. For example, to specify the dimension members that are required to retrieve the data of a measure that has the dimension as an input, you use a join
method to relate the dimension members to the measure. The join
method and the inputs of a Source
are described in "Inputs and Outputs of a Source".
A Source
has certain characteristics, such as a type and a data type, and it can have one or more inputs or outputs. This chapter describes these concepts. It also describes the different kinds of Source
objects and how you get them, and the join
method and other Source
methods and how you use those methods to specify a query.
The kinds of Source
objects that you use to specify data and to perform analysis, and the ways that you get them, are the following:
Primary Source
objects, which are returned by the getSource
method of an MdmSource
object such as an MdmDimension
or an MdmDimensionedObject
. A primary Source
provides access to the data that the MdmSource
represents. Getting primary Source
objects is usually the first step in creating a query. You then typically select elements from the primary Source
objects, thereby producing derived Source
objects.
Derived Source
objects, which you get by calling some of the methods of a Source
object. Methods such as join
return a new Source
that is derived from the Source
on which you call the method. All queries on the data store, other than a simple list of values specified by the primary Source
for an MdmDimension
, are derived Source
objects.
Fundamental Source
objects, which are returned by the getSource
method of a FundamentalMetadataObject
. These Source
objects represent the OLAP Java API data types.
List or range Source
objects, which are returned by the createConstantSource
, createListSource
, or createRangeSource
methods of a DataProvider
. Typically, you use this kind of Source
as the joined
or comparison
parameter to a join
method.
Empty, null, or void Source
objects. The empty and void Source
objects are returned by the getEmptySource
or getVoidSource
method of a DataProvider
, and the null Source
object is returned by the nullSource
method of a Source
. The empty Source
has no elements. The void Source
and a null Source
each has one element that has the value of null
. The difference between the void Source
and a null Source
is that the type of the void Source
is the FundamentalMetadataObject
for the Value data type and the type of a null Source
is the Source
whose nullSource
method returned it. Typically, you use these kinds of Source
objects as the joined
or comparison
parameter to a join
method.
Dynamic Source
objects, which are returned by the getSource
method of a DynamicDefinition
. A dynamic Source
is usually a derived Source
. It is generated by a Template
, which you use to create a dynamic query that you can revise after interacting with an end user.
Parameterized Source
objects, which are returned by the createSource
methods of a Parameter
. Like a list or range Source
, you use a parameterized Source
as a parameter to the join
method. Unlike a list or range Source
, however, you can change the value that the Parameter
represents after the join operation and thereby change the selection that the derived Source
represents. You can create a Cursor
for that derived Source
and retrieve the results of the query. You can then change the value of the Parameter
, and, without having to create a new Cursor
for the derived Source
, use that same Cursor
to retrieve the results of the modified query.
The Source
class has the following subclasses:
BooleanSource
DateSource
NumberSource
StringSource
These subclasses have different data types and implement Source
methods that require those data types. Each subclass also implements methods unique to it, such as the implies
method of a BooleanSource
or the indexOf
method of a StringSource
.
A Source
has a data type, a type, and an identifier (ID), and all Source
objects except the empty Source
have one or more elements. This topic describes these concepts. Some Source
objects have one or more inputs or outputs. Those complex concepts are discussed in "Inputs and Outputs of a Source".
All Source
objects, except the empty Source
, have one or more elements. An element of a Source
has a value, which can be null. For example, the Source
for the MdmPrimaryDimension
object for the CHANNEL_AWJ dimension has four elements. The values of those elements are the unique values of the members of the dimension, which are the following.
CHANNEL_PRIMARY::CHANNEL::TOTAL CHANNEL_PRIMARY::CHANNEL::CAT CHANNEL_PRIMARY::CHANNEL::DIR CHANNEL_PRIMARY::CHANNEL::INT
The FundamentalMetadataObject
class represents the data type of the values of the elements of an MdmSource
. The data type of a Source
is represented by a fundamental Source
. For example, a BooleanSource
has elements that have Java boolean
values. The data type of a BooleanSource
is the fundamental Source
that represents OLAP Java API Boolean values.
To get the fundamental Source
that represents the data type of a Source
, call the getDataType
method of the Source
. You can also get a fundamental Source
by calling the getSource
method of a FundamentalMetadataObject
.
The data type for a primary Source
is related to the SQL data type of the associated metadata object. For example, an MdmBaseAttribute
that has a SQL data type of VARCHAR2(30)
would produce a Source
whose data type is the fundamental Source
that represents OLAP Java API String values. The following code gets that fundamental Source
.
fmp.getStringDataType().getSource(); // fmp is the FundamentalMetadataProvider.
A typical use of a Source
for a data type is as the comparison Source
for a join or a recursive join operation. As such it represents the set of all values of that data type. For examples of the use of the getDataType
method, see Example 6-3, Example 6-5, and Example 6-11.
Along with a data type, a Source
has a type, which is the Source
from which the elements of the Source
are drawn. The type of a Source
determines whether the join
method can match the Source
with the input of another Source
. The only Source
that does not have a type is the fundamental Source
for the OLAP Java API Value data type, which represents the set of all values, and from which all other Source
objects ultimately descend. You can find the type by calling the getType
method of a Source
.
The type of a fundamental Source
is the data type of the Source
. The type of a list or range Source
is the data type of the values of the elements of the list or range Source
.
The type of a primary Source
is one of the following:
The fundamental Source
that represents the data type of the values of the elements of the primary Source
. For example, the type of the Source
returned by the getSource
method of a typical numeric MdmMeasure
is the fundamental Source
that represents the set of all OLAP Java API number values.
The Source
for the object that contains the primary Source
. For example, the type of the Source
returned by the getSource
method of an MdmLevelHierarchy
is the Source
for the MdmPrimaryDimension
that contains the hierarchy.
The type of a derived Source
is one of the following:
The base Source
, which is the Source
whose method returned the derived Source
. A Source
returned by the alias
, distinct
, extract
, join
, recursiveJoin
, or value
methods, or one of their shortcuts, has the base Source
as the type.
A fundamental Source
. The type of the Source
returned by methods such as position
and count
is the fundamental Source
for the OLAP Java API Integer data type. The type of the Source
returned by methods that make comparisons, such as eq
, le
, and so on, is the fundamental Source
for the Boolean data type. The type of the Source
returned by methods that perform aggregate functions, such as the NumberSource
methods total
and average
, is a fundamental Source
that represents the function.
A derived Source
that has the base Source
as the type is a subtype of the Source
from which it is derived. A derived Source that has a fundamental Source
as the type is a subtype of the fundamental Source
. You can use the isSubtypeOf
method to determine if a Source
is a subtype of another Source
.
For example, in Example 5-1 the myList
object is a list Source
. The example uses myList
to select values from prodHier
, a Source
for an MdmLevelHierarchy
of the MdmPrimaryDimension
for the PRODUCT_AWJ dimension. In the example, dp
is the DataProvider
.
Example 5-1 Using the isSubtypeOf Method
Source myList = dp.createListSource(new String[] { "PRODUCT_PRIMARY::FAMILY::LTPC", "PRODUCT_PRIMARY::FAMILY::DTPC", "PRODUCT_PRIMARY::FAMILY::ACC", "PRODUCT_PRIMARY::FAMILY::MON"}); Source prodSel = prodHier.selectValues(myList); if (prodSel.isSubtypeOf(prodHier)) println("prodSel is a subtype of prodHier."); else println("prodSel is not a subtype of prodHier.");
Because prodSel
is a subtype of prodHier
, the condition in the if
statement is true and the example displays the following:
prodSel is a subtype of prodHier.
The type of myList
is the fundamental String Source
. The type of prodHier
is the Source
for the PRODUCT_AWJ dimension. The type of prodSel
is prodHier
because the elements of prodSel
are derived from the elements of prodHier
.
The supertype of a Source
is the type of the type of a Source
, and so on, up through the types to the Source
for the fundamental Value data type. For example, the fundamental Value Source
is the type of the fundamental String Source
, which is the type of prodHier
, which is the type of prodSel
. The fundamental Value Source
and the fundamental String Source
are both supertypes of prodSel
. The prodSel
Source
is a subtype of prodHier
, and of the fundamental String Source
, and of the fundamental Value Source
.
A Source
has an identification, an ID, which is a String
that uniquely identifies it during the current connection to the database. You can get the identification by calling the getID
method of a Source
. For example, the following code gets the identification of the Source
for the MdmPrimaryDimension
for the PRODUCT_AWJ dimension and displays the value.
println("The Source ID of prodDim is " + prodDim.getID());
The preceding code displays the following:
The Source ID of prodDim is Hidden..GLOBAL.PRODUCT_AWJ
Each Source
also has a SourceDefinition
object, which records information about the Source
. Oracle OLAP uses this information internally. For example, the SourceDefinition
of a derived Source
records the parameters of the join operation that produced the Source
, such as the base Source
, the joined Source
, the comparison Source
, the comparison rule, and the value of the visible
parameter.
The DynamicDefinition
class is a subclass of SourceDefinition
. An OLAP Java API client application uses the DynamicDefinition
of a Template
to get the dynamic Source
of the Template
.
An input of a Source
indicates that the elements of the Source
have a relation to those of another Source
. An output of a Source
contains elements from which values of the Source
with the output are derived. A Source
with one or more outputs is somewhat like an array of arrays.
A Source
can have inputs and it can have outputs. The inputs and the outputs of a Source
are other Source
objects.
The inputs and outputs of a base Source
influence the elements of a Source
that you derive from that base Source
. To derive a Source
, you use methods of the base Source
. The derived Source
can have outputs or inputs or both or neither, depending on the method and the parameters of the method.
Some Source
methods, such as the value
and position
methods, return a Source
that has an input. The join
and recursiveJoin
methods can return a Source
that has an output. If the join operation involves a Source
with an input and a Source
that matches with that input, then the input acts as a filter in producing the elements of the derived Source
.
This topic describes the join
method, the concepts of outputs and inputs, and the matching of inputs. It provides examples of producing Source
objects that have outputs, Source
objects that have inputs, and join operations that match an input with a Source
.
With the join
method, you join the elements of one Source
with those of another Source
to produce a derived Source
. The derived Source
could have inputs or outputs. The elements of the derived Source
, and whether it has any inputs or outputs, depend on the values of the parameters that you pass to the join
method.
The full signature of the join
method is the following.
Source join(Source joined, Source comparison, int comparisonRule, boolean visible)
The Source
on which you call the join
method is the base of the join operation. The parameters of the method are the following.
The joined
parameter is a Source
object. The join
method joins the elements of the base Source
and the elements of the joined Source
, with results that are determined by the values of the other join
parameters. If the values of the joined Source
are not related to the values of the base Source
, that is, if neither the joined Source
nor the base Source
matches with an input of the other, then the join produces a Cartesian product of the elements of the base and the joined Source
objects. The examples in the "Outputs of a Source" topic demonstrate this kind of join operation.
If the values of the joined Source
are related to the values of the base Source
, that is, if either the joined Source
or the base Source
is an input of the other, then the elements of the derived Source
are the result of the matching of the input. The examples in "Matching a Source with an Input" demonstrate this kind of join operation.
The comparison
parameter is another Source
object. The join operation compares the values of the elements of the comparison Source
to the values of the joined Source
. The values that are the same in the joined and comparison objects participate in the join operation or are removed from participation, depending on the value of the comparisonRule
parameter.
The value of the comparisonRule
parameter specifies which values of the joined Source
participate in the join operation. The comparisonRule
value also determines the sort order of the participating values. The comparison rule is one of the static constant fields of the Source
class. The basic comparison rules are the following.
COMPARISON_RULE_SELECT
, which specifies that only the elements of the joined Source
that are also in the comparison Source
participate in the join operation.
COMPARISON_RULE_REMOVE
, which specifies that only the elements of the joined Source
that are not in the comparison Source
participate in the join operation.
The other comparison rules are all select operations that sort the resulting values in various ways. Those rules are the following.
The visible
parameter is a boolean
value that specifies whether the joined Source
appears as an output of the Source
that is derived by the join operation. If the value of the visible
parameter is true
, then the derived Source
has an output that contains the elements drawn from the joined Source
. If the value is false
, then the derived Source
does not have an output for the joined Source
.
The join
method returns a derived Source
that has the values of the elements of the base Source
that are specified by the parameters of the method. Those values are the base values of the derived Source
.
If the value of the visible
parameter of the join
method is true
, then the joined Source
becomes an output of the derived Source
. The elements of the derived Source
then have the values of the output and the base values, as specified by the other parameters of the join operation.
A derived Source
can have from zero to many outputs. A Source
that is an output can itself have outputs. You can get the outputs of a Source
by calling the getOutputs
method, which returns a List
of Source
objects.
The examples in this "Outputs of a Source" topic all have simple join operations that produce Source
objects that have one or more outputs. Because none of the Source
objects in the join operations have inputs, the values of the derived Source
objects produced by the join operations are the Cartesian products of the base and the joined Source
objects.
Very different results occur from a join operation that involves a Source
that has an input and a Source
that matches with that input. For examples of Source
objects with inputs and the matching of inputs, see "Inputs of a Source" and "Matching a Source with an Input".
Example 5-2 uses the simplest signature of the join
method to produce a Source
that has one output. The example creates a list Source
, letters
, that has three elements, the values of which are A, B, and C. It also creates a list Source
, names
, that has three elements, the values of which are Stephen, Leo, and Molly.
Example 5-2 A Simple Join That Produces a Source with an Output
Source letters = dp.createListSource(new String[] {"A", "B", "C"}); Source names = dp.createListSource(new String[] {"Stephen", "Leo", "Molly"}); Source lettersWithNames = letters.join(names); // Oracle OLAP translates this shortcut signature of the join method into the // following full signature, where dp is the DataProvider for the session. // Source letters.join(names, // dp.getEmptySource(), // Source.COMPARISON_RULE_REMOVE, // true);
The letters.join(names)
operation joins the elements of the base Source
, letters
, and the joined Source
, names
. Because the comparison Source
has no elements, the join operation does not remove any of the elements that are in the joined Source
in producing the derived Source
. (The comparison Source
is the empty Source
that is returned by the dp.getEmptySource()
parameter of the full join
signature shown in the example.) The resulting derived Source
, lettersWithNames
, is the Cartesian product of the elements of the base letters
and the joined names
. Because both letters
and names
have three elements, the number of elements in lettersWithNames
is nine.
Because the visible
parameter of letters.join(names)
is true
, the derived Source
has an output. Because no elements
were removed from the joined Source
, the derived Source
has the values of all of the elements of the joined Source
.
A Cursor
for a Source
has the same structure as the Source
. A Cursor
for the lettersWithNames
Source
has a ValueCursor
for the base values of the derived Source
and a ValueCursor
for the output values. The following table presents the values of the ValueCursor
objects. The table includes headings that are not in the ValueCursor
objects.
Output Values Base Values Stephen A Stephen B Stephen C Leo A Leo B Leo C Molly A Molly B Molly C
Example 5-3 demonstrates using a comparison Source
that has values and the comparison rule COMPARISON_RULE_SELECT
. The example uses the letter
and names
Source
objects from Example 5-2 and adds the someNames
Source
. It uses someNames
as the comparison Source
. The output of the Source
derived from the join operation has only the names that are in both the joined Source
and the comparison Source
.
Example 5-3 A Simple Join That Selects Elements of the Joined Source
Source someNames = dp.createListSource(new String[] {"Stephen", "Molly"}); Source lettersAndSelectedNames = letters.join(names, someNames, Source.COMPARISON_RULE_SELECT, true);
A Cursor
for the lettersAndSelectedNames
Source
has the values specified by the Source
. The following table presents the Cursor
values and has headings added.
Output Values Base Values Stephen A Stephen B Stephen C Molly A Molly B Molly C
Example 5-4 demonstrates using a comparison Source
that has values and the comparison rule COMPARISON_RULE_REMOVE
. That comparison rule removes from participation in the join operation those values that are the same in the joined and in the comparison Source
objects. The output of the derived Source
therefore has only the name from the joined Source
that is not in the comparison Source
.
The example has the same base, joined, and comparison Source
objects as Example 5-3.
Example 5-4 A Simple Join That Removes Elements of the Joined Source
Source lettersAndNamesWithoutRemovedNames = letters.join(names, someNames, Source.COMPARISON_RULE_REMOVE, true);
A Cursor
for the lettersAndNamesWithoutRemovedNames
Source
has the values specified by the Source
. The following table presents the values and has headings added.
Output Values Base Values Leo A Leo B Leo C
If you join a Source
to a Source
that has an output, and if the visible
parameter
is true
, then the join operation produces a Source
that has the joined Source
as an additional output. The additional output becomes the first output, as shown in Example 5-5.
Example 5-5 uses the Source
objects from Example 5-3 and creates another list Source
, colors
, that contains the names of two colors. The example joins the colors
Source
to the lettersWithSelectedNames
Source
to produce the lettersWithSelectedNamesAndColors
Source
.
The lettersWithSelectedNames
Source
has names
as an output. The lettersWithSelectedNamesAndColors
Source
has both colors
and names
as outputs. The first output is colors
and the second output is names
.
Example 5-5 A Simple Join That Produces a Source with Two Outputs
Source colors = dp.createListSource(new String[] {"Green", "Maroon"}); Source lettersWithSelectedNames = letters.join(names, someNames, Source.COMPARISON_RULE_SELECT, true); Source lettersWithSelectedNamesAndColors = lettersWithSelectedNames.join(colors);
A Cursor
for the lettersWithSelectedNamesAndColors
Source
has the values shown in the following table. The table has headings added.
Output 1 Values Output 2 Values Base Values Green Stephen A Green Stephen B Green Stephen C Green Molly A Green Molly B Green Molly C Maroon Stephen A Maroon Stephen B Maroon Stephen C Maroon Molly A Maroon Molly B Maroon Molly C
If the visible
parameter of a join
method is false
, then the joined Source
participates in the join operation but does not appear as an output of the Source
derived by the join. Example 5-6 uses the joinHidden
shortcut method to join the lettersWithSelectedNames
and the colors
Source
objects from Example 5-5. The example includes in a comment the full join
signature for the joinHidden
shortcut.
Example 5-6 A Simple Join That Hides An Output
Source lettersWithSelectedNamesAndHiddenColors = lettersWithSelectedNames.joinHidden(colors); // The full signature of the joinHidden shortcut method is // Source result = base.join(joined, // dp.getEmptySource(), // Source.COMPARISON_RULE_REMOVE, // false); // So if Source base = lettersWithSelectedNames and // Source joined = colors, then the result Source is the same as the // lettersWithSelectedNamesAndHiddenColors Source.
A Cursor
for the lettersWithSelectedNamesAndHiddenColors
Source
has the values shown in the following table. The table has headings added.
Note that the derived lettersWithSelectedNamesAndHiddenColors
Source
still has twelve elements, even though the values for the colors
Source
do not appear as output values. The derived Source
has one set of the six values of the lettersWithSelectedNames
Source
for each value of the hidden colors
Source
.
Example 5-5 displays the following output.
Output Values Base Values Stephen A Stephen B Stephen C Molly A Molly B Molly C Stephen A Stephen B Stephen C Molly A Molly B Molly C
The examples in the "Outputs of a Source" topic all produce derived Source
objects that have elements that are the Cartesian product of the unrelated base and joined Source
objects. While such an operation can be useful, a more powerful aspect of Source
objects is the ability to relate the elements of one Source
to another Source
. When such a relationship exists, you can derive other Source
objects that are the result of operations between the related elements. For example, you can derive a Source
that contains only selected elements of another Source
. This relationship between elements is represented by the input of a Source
.
A Source
with an input is an incomplete specification of data. The input represents the type of Source
that can have the elements that a join operation requires to complete the data specification. Before you can retrieve the data with a Cursor
, you must match the input with a Source
that has the elements that complete the specification.
You match an input with a Source
by using the join
or recursiveJoin
method. The match occurs between the base Source
and the joined Source
.
The matching of an input acts as a filter so that the Source
derived by the join operation has only the elements of the base Source
whose values are related to those of the elements of the joined Source
. The rules related to matching a Source
with an input are described in "Matching a Source with an Input". That topic has examples that produce derived Source
objects that are the result of the matching of an input.
A Source
can have from zero to many inputs. You can get all of the inputs of a Source
by calling the getInputs
method.
Some primary Source
objects have inputs. You can derive a Source
that has an input by using some methods of the Source
class.
The primary Source
objects for the MdmDimensionedObject
subclasses MdmAttribute
and MdmMeasure
have inputs. The primary Source
for an MdmAttribute
has one input. The primary Source
for an MdmMeasure
has one or more inputs.
The inputs of an MdmAttribute
or an MdmMeasure
are the Source
objects for the MdmPrimaryDimension
objects that dimension the attribute or measure. To get the value of an attribute or a measure, you must join the attribute or measure with a Source
that contains the related dimension members. The join operation matches the input of the attribute or measure with the Source
that contains the dimension members. Example 5-7 matches the input of an attribute with the dimension of that attribute. Example 5-8 matches the inputs of a measure with the dimensions of that measure.
Some Source
methods always return a Source
that has an input. The Source
returned by the extract
, position
, or value
method has the base Source
as an input. You can use these methods to produce a Source
whose elements are derived, or filtered, from the elements of another Source
.
The value
method returns a Source
that has the elements of the base Source
and has the base Source
as an input. You typically use the Source
returned by the value
method as the base or joined Source
of a join
method, or sometimes as the comparison Source
. Several examples in this chapter and in Chapter 6 use the value
method.
The position
method returns a Source
that has the position of each element of the base Source
and that has the base Source
as an input. For an example of using the position
method, see Example 6-4.
You use the extract
method when elements of the Source
objects that you want to join have Source
objects as values. For examples of using the extract
method, see Example 5-12, Example 6-8, Example 6-13, and Example 6-14.
The input of a Source
derived by the position
or value
method, and an input intrinsic to an MdmDimensionedObject
, are regular inputs. A regular input relates the elements of the Source
with the input to the elements of the Source
that matches with the input. You can get the regular inputs by calling the getRegularInputs
method.
The input of a Source
returned by the extract
method is an extraction input. You can get the extraction inputs by calling the getExtractionInputs
method.
In a join operation, the matching of a Source
with an input occurs only between the base Source
and the joined Source
. A Source
matches with an input if one of the following conditions is true.
The Source
is the same object as the input or it is a subtype of the input.
The Source
has an output that is the same object as the input or the output is a subtype of the input.
The join operation looks for the conditions in the order shown in the preceding list. It searches the list of outputs of the Source
recursively, including any outputs of an output, looking for a match with the input. The search ends with the first matching Source
. An input can match with only one Source
.
When a Source
with an input is joined to a Source
that matches with the input, the derived Source
returned by the join
method has the elements of the base that are related to the elements specified by the parameters of the method. The derived Source
does not have the input.
Matching a Source
with an input does not affect the outputs of the base Source
or the joined Source
. If a base Source
has an output that matches with the input of the joined Source
, then the resulting Source
does not have the input but it does have the output. If the base Source
or the joined Source
in a join operation has an input that is not matched in the operation, then the unmatched input is an input of the resulting Source
.
The comparison Source
of a join
method does not participate in the input matching. If the comparison Source
has an input, then that input is not matched and the Source
returned by the join
method has that same input.
Example 5-7 demonstrates the joining of the Source
for an MdmBaseAttribute
to the Source
for an MdmPrimaryDimension
. The example gets the local value attribute from the MdmPrimaryDimension
for the CHANNEL_AWJ dimension. The Source
for the attribute, locValAttr
, has the Source
for the MdmPrimaryDimension
as an input.
In the example, locValAttr
is the base Source
of the join operation and chanDim
is the joined Source
. Because chanDim
is an instance of the Source
for the MdmPrimaryDimension
for the CHANNEL_AWJ dimension, chanDim
matches with the input of locValAttr
. The result of the join is dimMembersWithLocalValue
, which has chanDim
as an output and does not have any inputs.
The locValAttr
Source
has four elements because each of the four members of the CHANNEL_AWJ dimension has a different local value. The Source
derived by the join operation, dimMembersWithLocalValue
, has four elements. The value of each element is the dimension member and the related attribute value. The dimension member is a value from the output and the attribute value is from the base.
Example 5-7 demonstrates matching the input of a base Source
with the joined Source
. In the example, mdmDBSchema
is the MdmDatabaseSchema
for the GLOBAL schema.
Example 5-7 Getting an Attribute for a Dimension Member
MdmStandardDimension mdmChanDim = mdmDBSchema.findOrCreateStandardDimension("CHANNEL_AWJ"); Source chanDim = mdmChanDim.getSource(); Source locValAttr = mdmChanDim.getLocalValueAttribute().getSource(); Source dimMembersWithLocalValue = locValAttr.join(chanDim);
A Cursor
for the dimMembersWithLocalValue
Source
has the values shown in the following table. The output values are the unique dimension member values derived from the joined Source
, chanDim
. The base values are derived from the base Source
, locValAttr
. The table has headings added.
Output Values Base Values CHANNEL_PRIMARY::TOTAL_CHANNEL::TOTAL TOTAL CHANNEL_PRIMARY::CHANNEL::CAT CAT CHANNEL_PRIMARY::CHANNEL::DIR DIR CHANNEL_PRIMARY::CHANNEL::INT INT
Example 5-8 demonstrates getting values from a measure. The example gets the MdmCube
that contains the UNIT_PRICE measure and gets the MdmBaseMeasure
for the measure from that cube. The cube, and the measures of the cube, are dimensioned by the PRODUCT_AWJ and TIME_AWJ dimensions. The example gets the MdmPrimaryDimension
objects for those dimensions and gets the Source
objects for those metadata objects.
The Source
for the measure, unitPrice
, has the Source
objects for the two MdmPrimaryDimension
objects as inputs. The example joins the Source
for the measure with the Source
objects for the dimensions. The join operations match the inputs of the measure with the Source
objects for the dimensions.
The example first joins the Source
for the PRODUCT_AWJ dimension to the Source
for the measure. That unitPrice.join(prodDim)
operation derives a Source
that has base values from unitPrice
and has prodDim
as an output. It also has the Source
for the TIME_AWJ dimension as an input. The next join operation joins the Source
derived by unitPrice.join(prodDim)
with timeDim
, the Source
for the TIME_AWJ dimension. That join operation matches the input of the Source
derived by unitPrice.join(prodDim)
with timeDim
.
The Source
derived by the second join operation is pricesByProductAndTime
. That Source
has no inputs and has the Source
objects for the PRODUCT_AWJ and TIME_AWJ dimensions as outputs. A Cursor
for pricesByProductAndTime
contains the price of each product value for every time value.
The example finally calls the count
method of pricesByProductAndTime
. That method returns the NumberSource
numPricesByProductAndTime
, which contains the number of elements of the pricesByProductAndTime
Source
. A Cursor
for the numPricesByProductAndTime
Source
contains the value 4998, which is the number of measure values for the product and time tuples.
Example 5-8 demonstrates matching the inputs of the base Source
with the joined Source
. In the example, mdmDBSchema
is the MdmDatabaseSchema
for the GLOBAL schema.
Example 5-8 Getting Measure Values
MdmCube mdmPriceCube = mdmDBSchema.findOrCreateCube("PRICE_CUBE_AWJ"); MdmBaseMeasure mdmUnitPrice = mdmPriceCube.findOrCreateBaseMeasure("UNIT_PRICE"); MdmStandardDimension mdmProdDim = mdmDBSchema.findOrCreateStandardDimension("PRODUCT_AWJ"); MdmTimeDimension mdmTimeDim = mdmDBSchema.findOrCreateTimeDimension("TIME_AWJ"); Source prodDim = mdmProdDim.getSource(); Source timeDim = mdmTimeDim.getSource(); Source unitPrice = mdmUnitPrice.getSource(); Source pricesByProductAndTime = unitPrice.join(prodDim).join(timeDim); NumberSource numPricesByProductAndTime = pricesByProductAndTime.count();
To produce a Source
that contains only the measure values for certain products and times, you need to join the Source
for the measure with Source
objects that specify the dimension values that you want. You can produce such a selection by using methods of the primary Source
for the dimension. One means of producing a Source
that represents a selection of values of a Source
is to use the value
method.
In Example 5-9, the lettersValue
Source
is returned by the letters.value()
method. The lettersValue
Source
has letters
as an input. The input represents a relation between the values of the Source
with the input and the values of the Source
that matches with the input.
In the example, the join operation has letters
as the base Source
and lettersValue
as the joined Source
. The base Source
, letters
, matches with the input of lettersValue
, which is also letters
, because they are the same. The Source
produced by the join operation, lettersByLettersValue
has lettersValue
as an output. It does not have an input. Each element of lettersByLettersValue
has a base value from letters
and the related value from lettersValue
.
Example 5-9 Using the value Method to Relate a Source to Itself
Source letters = dp.createListSource(new String[] {"A", "B", "C"}); Source lettersValue = letters.value(); Source lettersByLettersValue = letters.join(lettersValue);
A Cursor
for the lettersByLettersValue
Source
has the values shown in the following table. The table has headings added.
Output Values Base Values A A B B C C
Because lettersByLettersValue
contains only those values of the base and joined Source
objects that are related, the base values of the Cursor
for lettersByLettersValue
Source
are the same as the output values. If the base and joined Source
objects had been unrelated, as in letters.join(letters)
, then the Source
produced by the join operation would contain the Cartesian product of the base and joined Source
objects.
By using the value
method, you can derive a Source
that is a selection of the elements of another Source
. Example 5-10 selects two elements from the Source
for the PRODUCT_AWJ dimension from Example 5-7. The example demonstrates a base Source
matching with the input of the joined Source
.
Example 5-10 Using the value Method to Select Elements of a Source
Source productsToSelect = dp.createListSource(new String[] {"PRODUCT_PRIMARY::ITEM::ENVY EXE", "PRODUCT_PRIMARY::ITEM::ENVY STD"}); Source selectedProducts = prodDim.join(prodDim.value(), productsToSelect, Source.COMPARISON_RULE_SELECT, false); // Hide the output.
A Cursor
for the productsToSelect
Source
has the following values.
PRODUCT_PRIMARY::ITEM::ENVY EXE PRODUCT_PRIMARY::ITEM::ENVY STD
A Cursor
for the selectedProducts
Source
has the following values.
PRODUCT_PRIMARY::ITEM::ENVY EXE PRODUCT_PRIMARY::ITEM::ENVY STD
The two Source
objects contain the same values. However, the types of the objects are different. The type of the productsToSelect
Source
is the Source
for the FundamentalMetadataObject
for the String data type. The type of the selectedProducts
Source
is prodDim
because selectedProducts
is derived from prodDim
. Therefore, selectedProducts
is a subtype of prodDim
and as such it can match with a Source
that has the Source
for the PRODUCT_AWJ dimension as an input, as shown in Example 5-11.
Example 5-11 selects elements from the Source
objects for two dimensions and then gets the measure values for the selected dimension members. Example 5-11 uses the same dimensions and measure as in Example 5-8. In Example 5-11, however, the Source
objects that match with the inputs of the Source
for the measure are not the Source
objects for the dimensions. Instead they are subtypes of the Source
objects for the dimensions. The subtypes specify selected members of the dimensions. The Source
that is derived by joining the measure with the dimensions, pricesForSelectedProductsAndTimes
, has six elements, which specify only the measure values for the two products for the three time values, instead of the 4998 elements of the pricesByProductAndTime
Source
in Example 5-8. In Example 5-11, mdmDBSchema
is the MdmDatabaseSchema
for the GLOBAL schema.
Example 5-11 Using Derived Source Objects to Select Measure Values
// Create lists of product and time dimension members. Source productsToSelect = dp.createListSource(new String[] {"PRODUCT_PRIMARY::ITEM::ENVY EXE", "PRODUCT_PRIMARY::ITEM::ENVY STD"}); Source timesToSelect = dp.createListSource(new String[] {"CALENDAR_YEAR::MONTH::2000.01", "CALENDAR_YEAR::MONTH::2001.01", "CALENDAR_YEAR::MONTH::2002.01"}); // Get the PRICE_CUBE_AWJ cube. MdmCube mdmPriceCube = mdmDBSchema.findOrCreateCube("PRICE_CUBE_AWJ"); // Get the UNIT_PRICE measure from the cube. MdmBaseMeasure mdmUnitPrice = mdmPriceCube.findOrCreateBaseMeasure("UNIT_PRICE"); // Get the PRODUCT_AWJ and TIME_AWJ dimensions. MdmStandardDimension mdmProdDim = mdmDBSchema.findOrCreateStandardDimension("PRODUCT_AWJ"); MdmTimeDimension mdmTimeDim = mdmDBSchema.findOrCreateTimeDimension("TIME_AWJ"); // Get the Source objects for the dimensions and the measure. Source prodDim = mdmProdDim.getSource(); Source timeDim = mdmTimeDim.getSource(); Source unitPrice = mdmUnitPrice.getSource(); // Using the value method, derive Source objects that specify the selected // dimension members. Source selectedProducts = prodDim.join(prodDim.value(), productsToSelect, Source.COMPARISON_RULE_SELECT, false); Source selectedTimes = timeDim.join(timeDim.value(), timesToSelect, Source.COMPARISON_RULE_SELECT, false); // Derive a Source that specifies the unitPrice values for the selected products // and times. Source pricesForSelectedProductsAndTimes = unitPrice.join(selectedProducts) .join(selectedTimes);
A Cursor
for the pricesForSelectedProductsAndTimes
Source
has the values shown in the following table. The table has headings added.
Month Product Price ----------------------------- ------------------------------- ------- CALENDAR_YEAR::MONTH::2000.01 PRODUCT_PRIMARY::ITEM::ENVY EXE 3358.02 CALENDAR_YEAR::MONTH::2000.01 PRODUCT_PRIMARY::ITEM::ENVY STD 3000.11 CALENDAR_YEAR::MONTH::2001.01 PRODUCT_PRIMARY::ITEM::ENVY EXE 3223.28 CALENDAR_YEAR::MONTH::2001.01 PRODUCT_PRIMARY::ITEM::ENVY STD 2426.07 CALENDAR_YEAR::MONTH::2002.01 PRODUCT_PRIMARY::ITEM::ENVY EXE 3008.95 CALENDAR_YEAR::MONTH::2002.01 PRODUCT_PRIMARY::ITEM::ENVY STD 2140.71
The extract
method derives a Source
that has the base Source
as an input. You use the extract
method when the values of the elements of a Source
are Source
objects themselves.
Example 5-12 uses the selectValues
method to derive two selections of elements from a StringSource
for the PRODUCT_AWJ dimension. The selectValues
method is a shortcut for the full join
signature of the methods in Example 5-10 and Example 5-11 that produce the selectedProducts
and selectedTimes
Source
objects.
Example 5-12 creates a list Source
, sourcesToCombine
, that has the two derived Source
objects as element values. The sourcesToCombine.extract()
method produces sourcesToCombineWithAnInput
, which is a Source
that has sourcesToCombine
as an input. The join operation sourcesToCombineWithAnInput.joinHidden(sourcesToCombine)
matches the input of sourcesToCombineWithAnInput
with the joined sourcesToCombine
and produces combinedSources
, which has no inputs or outputs. A shortcut for this combining of Source
elements is the appendValues
method.
Example 5-12 Extracting Elements of a Source
MdmStandardDimension mdmProdDim = mdmDBSchema.findOrCreateStandardDimension("PRODUCT_AWJ"); StringSource prodDim = (StringSource) mdmProdDim.getSource(); Source productsToSelect = prodDim.selectValues(new String[] {"PRODUCT_PRIMARY::ITEM::ENVY ABM", "PRODUCT_PRIMARY::ITEM::ENVY EXE", "PRODUCT_PRIMARY::ITEM::ENVY STD"}); Source moreProductsToSelect = prodDim.selectValues(new String[] {"PRODUCT_PRIMARY::ITEM::SENT FIN", "PRODUCT_PRIMARY::ITEM::SENT MM", "PRODUCT_PRIMARY::ITEM::SENT STD"}); Source sourcesToCombine = dp.createListSource(new Source[] {productsToSelect, moreProductsToSelect}); Source sourcesToCombineWithAnInput = sourcesToCombine.extract(); Source combinedProducts = sourcesToCombineWithAnInput.joinHidden(sourcesToCombine);
A Cursor
for the combinedProducts
Source
has the following values.
PRODUCT_PRIMARY::ITEM::ENVY ABM PRODUCT_PRIMARY::ITEM::ENVY EXE PRODUCT_PRIMARY::ITEM::ENVY STD PRODUCT_PRIMARY::ITEM::SENT FIN PRODUCT_PRIMARY::ITEM::SENT MM PRODUCT_PRIMARY::ITEM::SENT STD
Parameterized Source
objects provide a way of specifying a query and retrieving different result sets for the query by changing the set of elements specified by the parameterized Source
. You create a parameterized Source
with a createSource
method of the Parameter
. The Parameter
supplies the value that the parameterized Source
specifies.
Example 5-13 in this topic is a very simple demonstration of using a Parameter
object. A typical use of a Parameter
is to specify the page edges of a cube, as shown in Example 6-9. Another use of a Parameter
is to fetch from the server only the set of elements that you currently need. Example 6-15 demonstrates using Parameter
objects to fetch different sets of elements.
When you create a Parameter
object, you supply an initial value for the Parameter
. You then create the parameterized Source
using the Parameter
. You include the parameterized Source
in specifying a query. You create a Cursor
for the query. You can change the value of the Parameter
with the setValue
method, which changes the set of elements that the query specifies. Using the same Cursor
, you can then retrieve the new set of values.
Example 5-13 demonstrates the use of a Parameter
and a parameterized Source
to specify a member in a dimension. The example gets the MdmStandardDimension
for the PRODUCT_AWJ dimension and gets the Source
for the MdmStandardDimension
cast as a StringSource
.
The example creates a StringParameter
object that has a dimension member as the initial value. It then creates a parameterized Source
, paramProdSel
, by using the createSource
method of the StringParameter
. Next it uses paramProdSel
as the comparison Source
in a join operation that selects the dimension member.
The example gets the Source
for the local value attribute of the dimension. It joins that Source
, locValAttr
, with paramProdSel
. That join operation produces the dimMemberWithLocalValue
Source
.
The example creates a Cursor
for dimMemberWithLocalValue
and displays the value of the Cursor
. After resetting the Cursor
position and changing the value of the prodParam
StringParameter
, the example displays the value of the Cursor
again.
The dp
object is the DataProvider
. The getContext
method gets a Context11g
object that has a method that commits the current Transaction
and a method that displays the values of a Cursor
.
Example 5-13 Using a Parameterized Source to Change a Dimension Selection
MdmStandardDimension mdmProdDim = mdmDBSchema.findOrCreateStandardDimension("PRODUCT_AWJ"); StringSource prodDim = (StringSource) mdmProdDim.getSource(); StringParameter prodParam = new StringParameter(dp, "PRODUCT_PRIMARY::FAMILY::LTPC"); Source prodParamSrc = prodParam.createSource(); Source paramProdSel = prodDim.join(prodDim.value(), prodParamSrc); Source locValAttr = mdmProdDim.getLocalValueAttribute().getSource(); Source dimMemberWithLocalValue = locValAttr.join(paramProdSel); // Commit the Transaction. getContext().commit(); // Create a Cursor for the Source. CursorManager cursorMngr = dp.createCursorManager(dimMemberWithLocalValue); Cursor cursor = cursorMngr.createCursor(); // Display the value of the Cursor. getContext().displayCursor(cursor); // Change the product parameter value. prodParam.setValue("PRODUCT_PRIMARY::FAMILY::DTPC"); // Reset the Cursor position to 1 cursor.setPosition(1); // Display the value of the Cursor again. getContext().displayCursor(cursor);
The Cursor
for dimMemberWithLocalValue
displays the following.
PRODUCT_PRIMARY::FAMILY::LTPC,LTPC
After changing the value of the StringParameter
and resetting the position of the Cursor
, the Cursor
for dimMemberWithLocalValue
displays the following.
PRODUCT_PRIMARY::FAMILY::DTPC,DTPC