ADDRESS

RAW(4 | 8)

Address of the handle to the parent for this cursor

HASH_VALUE

NUMBER

Hash value of the parent statement in the library cache. The two columns ADDRESS and HASH_VALUE can be used to join with V$SQLAREA to add the cursor-specific information.

SQL_ID

VARCHAR2(13)

SQL identifier of the parent statement in the library cache

PLAN_HASH_VALUE

NUMBER

Numerical representation of the current SQL plan for this cursor. Comparing one PLAN_HASH_VALUE to another easily identifies whether or not two plans are the same (rather than comparing the two plans line by line)

FULL_PLAN_HASH_VALUE

NUMBER

Numeric representation of the complete SQL plan for this cursor. Comparing one FULL_PLAN_HASH_VALUE to another easily identifies whether or not two plans are the same (rather than comparing the two plans line by line). Note that the FULL_PLAN_HASH_VALUE cannot be compared across databases releases. It is not backward compatible.

CHILD_ADDRESS

RAW(4 | 8)

Address of the child cursor

CHILD_NUMBER

NUMBER

Number of the child cursor that uses this execution plan. The columns ADDRESS, HASH_VALUE, and CHILD_NUMBER can be used to join with V$SQL to add the child cursor-specific information.

TIMESTAMP

DATE

Date and time when the execution plan was generated

OPERATION

VARCHAR2(120)

Name of the internal operation performed in this step (for example, TABLE ACCESS)

OPTIONS

VARCHAR2(120)

A variation on the operation described in the OPERATION column (for example, FULL)

OBJECT_NODE

VARCHAR2(160)

Name of the database link used to reference the object (a table name or view name). For local queries that use parallel execution, this column describes the order in which output from operations is consumed.

OBJECT#

NUMBER

Object number of the table or the index

OBJECT_OWNER

VARCHAR2(128)

Name of the user who owns the schema containing the table or index

OBJECT_NAME

VARCHAR2(128)

Name of the table or index

OBJECT_ALIAS

VARCHAR2(261)

Alias for the object

OBJECT_TYPE

VARCHAR2(80)

Type of the object

OPTIMIZER

VARCHAR2(80)

Current mode of the optimizer for the first row in the plan (statement line), for example, CHOOSE. When the operation is a database access (for example, TABLE ACCESS), this column indicates whether or not the object is analyzed.

ID

NUMBER

A number assigned to each step in the execution plan

PARENT_ID

NUMBER

ID of the next execution step that operates on the output of the current step

DEPTH

NUMBER

Depth (or level) of the operation in the tree. It is not necessary to issue a CONNECT BY statement to get the level information, which is generally used to indent the rows from the PLAN_TABLE table. The root operation (statement) is level 0.

POSITION

NUMBER

Order of processing for all operations that have the same PARENT_ID

SEARCH_COLUMNS

NUMBER

Number of index columns with start and stop keys (that is, the number of columns with matching predicates)

COST

NUMBER

Cost of the operation as estimated by the optimizer's cost-based approach. For statements that use the rule-based approach, this column is null.

CARDINALITY

NUMBER

Estimate, by the cost-based optimizer, of the number of rows produced by the operation

BYTES

NUMBER

Estimate, by the cost-based optimizer, of the number of bytes produced by the operation

OTHER_TAG

VARCHAR2(140)

Describes the contents of the OTHER column. See EXPLAIN PLAN for values.

PARTITION_START

VARCHAR2(256)

Start partition of a range of accessed partitions

PARTITION_STOP

VARCHAR2(256)

Stop partition of a range of accessed partitions

PARTITION_ID

NUMBER

Step that computes the pair of values of the PARTITION_START and PARTITION_STOP columns

OTHER

VARCHAR2(4000)

Other information specific to the execution step that users may find useful. See EXPLAIN PLAN for values.

DISTRIBUTION

VARCHAR2(80)

Stores the method used to distribute rows from producer query servers to consumer query servers

CPU_COST

NUMBER

CPU cost of the operation as estimated by the optimizer's cost-based approach. For statements that use the rule-based approach, this column is null.

IO_COST

NUMBER

I/O cost of the operation as estimated by the optimizer's cost-based approach. For statements that use the rule-based approach, this column is null.

TEMP_SPACE

NUMBER

Temporary space usage of the operation (sort or hash-join) as estimated by the optimizer's cost-based approach. For statements that use the rule-based approach, this column is null.

ACCESS_PREDICATES

VARCHAR2(4000)

Predicates used to locate rows in an access structure. For example, start or stop predicates for an index range scan.

FILTER_PREDICATES

VARCHAR2(4000)

Predicates used to filter rows before producing them

PROJECTION

VARCHAR2(4000)

Expressions produced by the operation

TIME

NUMBER

Elapsed time (in seconds) of the operation as estimated by the optimizer's cost-based approach. For statements that use the rule-based approach, this column is null.

QBLOCK_NAME

VARCHAR2(128)

Name of the query block

REMARKS

VARCHAR2(4000)

Remarks

OTHER_XML

CLOB

Provides extra information specific to an execution step of the execution plan. The content of this column is structured using XML since multiple pieces of information can be stored there. This includes:

• Name of the schema against which the query was parsed

• Release number of the Oracle Database that produced the explain plan

• Hash value associated with the execution plan

• Name (if any) of the outline or the SQL profile used to build the execution plan

• Indication of whether or not dynamic statistics were used to produce the plan

• The outline data, a set of optimizer hints that can be used to regenerate the same plan

• Additional data that describes the relationship between rows in the plan table and subplans of adaptive plans. Note that in Oracle Database 12c, there will be extra rows in the plan table and V$SQL_PLAN.

EXECUTIONS

NUMBER

Number of times this cursor has been executed

LAST_STARTS

NUMBER

Number of times this operation has been started, during the last execution

STARTS

NUMBER

Number of times this operation has been started, accumulated over the past executions

LAST_OUTPUT_ROWS

NUMBER

Number of rows produced by the row source, during the last execution

OUTPUT_ROWS

NUMBER

Number of rows produced by the row source, accumulated over the past executions

LAST_CR_BUFFER_GETS

NUMBER

Number of buffers retrieved in consistent mode, during the last execution. Buffers are usually retrieved in consistent mode for queries.

CR_BUFFER_GETS

NUMBER

Number of buffers retrieved in consistent mode, accumulated over the past executions. Buffers are usually retrieved in consistent mode for queries.

LAST_CU_BUFFER_GETS

NUMBER

Number of buffers retrieved in current mode, during the last execution. Buffers are retrieved in current mode for statements such as INSERT, UPDATE, and DELETE.

CU_BUFFER_GETS

NUMBER

Number of buffers retrieved in current mode, accumulated over the past executions. Buffers are retrieved in current mode for statements such as INSERT, UPDATE, and DELETE.

LAST_DISK_READS

NUMBER

Number of physical disk reads performed by the operation, during the last execution

DISK_READS

NUMBER

Number of physical disk reads performed by the operation, accumulated over the past executions

LAST_DISK_WRITES

NUMBER

Number of physical disk writes performed by the operation, during the last execution

DISK_WRITES

NUMBER

Number of physical disk writes performed by the operation, accumulated over the past executions

LAST_ELAPSED_TIME

NUMBER

Elapsed time (in microseconds) corresponding to this operation, during the last execution

ELAPSED_TIME

NUMBER

Elapsed time (in microseconds) corresponding to this operation, accumulated over the past executions

POLICY

VARCHAR2(40)

Sizing policy for this work area:

• MANUAL

• AUTO

ESTIMATED_OPTIMAL_SIZE

NUMBER

Estimated size (in KB) required by this work area to execute the operation completely in memory (optimal execution). This is either derived from optimizer statistics or from previous executions.

ESTIMATED_ONEPASS_SIZE

NUMBER

Estimated size (in KB) required by this work area to execute the operation in a single pass. This is either derived from optimizer statistics or from previous executions.

LAST_MEMORY_USED

NUMBER

Memory size (in KB) used by this work area during the last execution of the cursor

LAST_EXECUTION

VARCHAR2(40)

Indicates whether this work area ran using OPTIMAL, ONE PASS, or under ONE PASS memory requirement (MULTI-PASS), during the last execution of the cursor

LAST_DEGREE

NUMBER

Degree of parallelism used, during the last execution of the cursor

TOTAL_EXECUTIONS

NUMBER

Number of times this work area was active

OPTIMAL_EXECUTIONS

NUMBER

Number of times this work area ran in optimal mode

ONEPASS_EXECUTIONS

NUMBER

Number of times this work area ran in one pass mode

MULTIPASSES_EXECUTIONS

NUMBER

Number of times this work area ran below the one pass memory requirement

ACTIVE_TIME

NUMBER

Average time this work area is active (in hundredths of a second)

MAX_TEMPSEG_SIZE

NUMBER

Maximum temporary segment size (in bytes) created by an instantiation of this work area. This column is null if this work area has never spilled to disk.

LAST_TEMPSEG_SIZE

NUMBER

Temporary segment size (in bytes) created in the last instantiation of this work area. This column is null if the last instantiation of this work area did not spill to disk.

CON_ID

NUMBER

The ID of the container to which the data pertains. Possible values include:

• 0: This value is used for rows containing data that pertain to the entire CDB. This value is also used for rows in non-CDBs.

• 1: This value is used for rows containing data that pertain to only the root

• n: Where n is the applicable container ID for the rows containing data

CON_DBID

NUMBER

The database ID of the PDB