13.34 FORALL Statement
The FORALL
statement runs one DML statement multiple times, with different values in the VALUES
and WHERE
clauses.
The different values come from existing, populated collections or host arrays. The FORALL
statement is usually much faster than an equivalent FOR
LOOP
statement.
Note:
You can use the FORALL
statement only in server programs, not in client programs.
Topics
Syntax
forall_statement ::=
bounds_clause ::=
Semantics
forall_statement
index
Name for the implicitly declared integer variable that is local to the FORALL
statement. Statements outside the FORALL
statement cannot reference index
. Statements inside the FORALL
statement can reference index
as an index variable, but cannot use it in expressions or change its value. After the FORALL
statement runs, index
is undefined.
dml_statement
A static or dynamic INSERT
, UPDATE
, DELETE
, or MERGE
statement that references at least one collection in its VALUES
or WHERE
clause. Performance benefits apply only to collection references that use index
as an index.
Every collection that dml_statement
references must have indexes that match the values of index
. If you apply the DELETE
, EXTEND
, or TRIM
method to one collection, apply it to the other collections also, so that all collections have the same set of indexes. If any collection lacks a referenced element, PL/SQL raises an exception.
Restriction on dml_statement
If dml_statement
is a dynamic SQL statement, then values in the USING
clause (bind variables for the dynamic SQL statement) must be simple references to the collection, not expressions. For example, collection
(
i
)
is valid, but UPPER(
collection
(
i
))
is invalid.
SAVE EXCEPTIONS
Lets the FORALL
statement continue even if some of its DML statements fail. For more information, see "Handling FORALL Exceptions After FORALL Statement Completes".
bounds_clause
Specifies the collection element indexes that provide values for the variable index
. For each value, the SQL engine runs dml_statement
once.
lower_bound .. upper_bound
Both lower_bound
and upper_bound
are numeric expressions that PL/SQL evaluates once, when the FORALL
statement is entered, and rounds to the nearest integer if necessary. The resulting integers must be the lower and upper bounds of a valid range of consecutive index numbers. If an element in the range is missing or was deleted, PL/SQL raises an exception.
INDICES OF collection [ BETWEEN lower_bound AND upper_bound ]
Specifies that the values of index
correspond to the indexes of the elements of collection
. The indexes need not be consecutive.
Both lower_bound
and upper_bound
are numeric expressions that PL/SQL evaluates once, when the FORALL
statement is entered, and rounds to the nearest integer if necessary. The resulting integers are the lower and upper bounds of a valid range of index numbers, which need not be consecutive.
Restriction on collection
If collection
is an associative array, it must be indexed by PLS_INTEGER
.
VALUES OF index_collection
Specifies that the values of index
are the elements of index_collection
, a collection of PLS_INTEGER
elements that is indexed by PLS_INTEGER
. The indexes of index_collection
need not be consecutive. If index_collection
is empty, PL/SQL raises an exception and the FORALL
statement does not run.
Examples
-
Example 12-8, "DELETE Statement in FORALL Statement"
-
Example 12-9, "Time Difference for INSERT Statement in FOR LOOP and FORALL Statements"
-
Example 12-10, "FORALL Statement for Subset of Collection"
-
Example 12-11, "FORALL Statements for Sparse Collection and Its Subsets"
-
Example 12-12, "Handling FORALL Exceptions Immediately"
-
Example 12-13, "Handling FORALL Exceptions After FORALL Statement Completes"
-
Example 12-26, "DELETE with RETURN BULK COLLECT INTO in FORALL Statement"
-
Example 12-28, "Anonymous Block Bulk-Binds Input Host Array"
Related Topics
In this chapter:
In other chapters: