PLAN_TABLE
is the default table for results of the EXPLAIN PLAN
statement. It is created by utlxplan.sql
, and it contains one row for each step in the execution plan.
Column | Datatype | NULL | Description |
---|---|---|---|
STATEMENT_ID |
VARCHAR2(30) |
Optional statement identifier specified in the EXPLAIN PLAN statement |
|
TIMESTAMP |
DATE |
Date and time when the EXPLAIN PLAN statement was issued |
|
REMARKS |
VARCHAR2(80) |
Place for comments that can be added to the steps of the execution plan | |
OPERATION |
VARCHAR2(30) |
Name of the operation performed at this step | |
OPTIONS |
VARCHAR2(255) |
Options used for the operation performed at this step; the string returned by the index cost function | |
OBJECT_NODE |
VARCHAR2(128) |
Name of the database link used to reference the object | |
OBJECT_OWNER |
VARCHAR2(30) |
Owner of the object | |
OBJECT_NAME |
VARCHAR2(30) |
Name of the object | |
OBJECT_INSTANCE |
NUMBER(38) |
Numbered position of the object name in the original SQL statement | |
OBJECT_TYPE |
VARCHAR2(30) |
Descriptive modifier that further describes the type of object | |
OPTIMIZER |
VARCHAR2(255) |
Current mode of the optimizer | |
SEARCH_COLUMNS |
NUMBER |
Number of index columns with start and stop keys (that is, the number of columns with matching predicates) | |
ID |
NUMBER(38) |
Identification number for this step in the execution plan | |
PARENT_ID |
NUMBER(38) |
ID of the next step that operates on the results of this step | |
POSITION |
NUMBER(38) |
Order of processing for steps with the same parent ID. For cost-based optimization, the value in the first row of the plan is the statement's execution cost. For rule-based optimization, the value is null in the first row. | |
COST |
NUMBER(38) |
Cost of the current operation estimated by the cost-based optimizer (CBO) | |
CARDINALITY |
NUMBER(38) |
Number of rows returned by the current operation (estimated by the CBO) | |
BYTES |
NUMBER(38) |
Number of bytes returned by the current operation | |
OTHER_TAG |
VARCHAR2(255) |
Describes the function of the SQL text in the OTHER column. Values for OTHER_TAG are:
|
|
PARTITION_START |
VARCHAR2(255) |
Start partition of a range of accessed partitions | |
PARTITION_STOP |
VARCHAR2(255) |
Stop partition of a range of accessed partitions | |
PARTITION_ID |
NUMBER(38) |
Step that has computed the pair of values of the PARTITION_START and PARTITION_STOP columns |
|
OTHER |
LONG |
Information about parallel execution slaves and parallel queries | |
DISTRIBUTION |
VARCHAR2(30) |
Distribution method | |
CPU_COST |
NUMBER(38) |
User-defined CPU cost | |
IO_COST |
NUMBER(38) |
User-defined I/O cost | |
TEMP_SPACE |
NUMBER(38) |
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(38) |
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. |