PLAN_TABLE is automatically created as a global temporary table to hold（保存） the output of an EXPLAIN PLAN statement for all users.PLAN_TABLE is the default sample（樣本） output table into which the EXPLAIN PLAN statement inserts rows describing（描述） execution plans.
While a PLAN_TABLE table is automatically set up for each user, you can use the SQL script utlxplan.sql to manually create a local PLAN_TABLE in your schema.
STATEMENT_ID
VARCHAR2(30)
Value of the optional STATEMENT_ID parameter specified in the EXPLAIN PLAN statement
PLAN_ID
NUMBER
Unique identifier of a plan in the database
TIMESTAMP
DATE
Date and time when the EXPLAIN PLAN statement was generated（產生）
REMARKS（注釋）
VARCHAR2(4000)
Any comment（注釋） (of up to 4000 bytes) you want to associate（關聯） with each step of the explained plan. This column is used to indicate whether an outline or SQL Profile was used for the query.
If you need to add or change a remark on any row of the PLAN_TABLE, then use the UPDATE statement to modify the rows of the PLAN_TABLE.
OPERATION
VARCHAR2(30)
Name of the internal（內部） operation performed（執行） in this step. In the first row generated for a statement, the column contains one of the following values:
DELETE STATEMENT
INSERT STATEMENT
SELECT STATEMENT
UPDATE STATEMENT
OPTIONS（選項）
VARCHAR2(255)
A variation（變動） on the operation described in the OPERATION column
OBJECT_NODE
VARCHAR2(128)
Name of the database link used to reference the object (a table name or view name). For local queries using parallel execution, this column describes the order in which output from operations is consumed（消費）.
OBJECT_OWNER
VARCHAR2(128)
Owner of the table or index
OBJECT_NAME
VARCHAR2(128)
Name of the table or index
OBJECT_ALIAS
VARCHAR2(261)
Unique alias（別名） of a table or view in a SQL statement. For indexes, it is the object alias of the underlying（底層） table.
OBJECT_INSTANCE
NUMBER(38)
Number corresponding（對應的） to the ordinal position（順序數位置） of the object as it appears in the original statement. The numbering proceeds（往前） from left to right, outer to inner with respect（遵守） to the original statement text. View expansion results in unpredictable（不可預知的） numbers.
OBJECT_TYPE
VARCHAR2(30)
Modifier that provides（提供） descriptive information about the object; for example, NON-UNIQUE for indexes
OPTIMIZER（優化器）
VARCHAR2(255)
Current mode of the optimizer
SEARCH_COLUMNS
NUMBER
Not currently used
ID
NUMBER(38)
A number assigned（分配） to each step in the execution plan
PARENT_ID
NUMBER(38)
ID of the next execution step that operates on the output of the ID step
DEPTH
NUMBER(38)
Depth（深度） of the operation in the row source tree that the plan represents. The value can be used for indenting the rows in a plan table report（表示）.
POSITION
NUMBER(38)
For the first row of output, this indicates the optimizer's estimated cost（優化器估計的消耗） of executing the statement. For the other rows, it indicates the position relative（相對的） to the other children of the same parent.
COST
NUMBER(38)
Cost of the operation as estimated by the optimizer's query approach（途徑）. Cost is not determined for table access operations. The value of this column does not have any particular unit of measurement（測量特定的單位）; it is merely（僅僅） a weighted value used to compare costs of execution plans. The value of this column is a function of the CPU_COST and IO_COST columns.
CARDINALITY
NUMBER(38)
Estimate by the query optimization approach of the number of rows accessed by the operation
BYTES
NUMBER(38)
Estimate by the query optimization approach of the number of bytes accessed by the operation
OTHER_TAG
VARCHAR2(255)
Describes the contents of the OTHER column:
SERIAL（順序的） - Serial execution. Currently, SQL is not loaded in the OTHER column for this case.
SERIAL_FROM_REMOTE - Serial execution at a remote site（位置）.
PARALLEL_FROM_SERIAL - Serial execution. Output of step is partitioned or broadcast（廣播） to parallel execution servers.
PARALLEL_TO_SERIAL - Parallel execution. Output of step is returned to serial query coordinator (QC)（查詢協調） process.
PARALLEL_TO_PARALLEL - Parallel execution. Output of step is repartitioned to second set of parallel execution servers.
PARALLEL_COMBINED（聯合）_WITH_PARENT - Parallel execution; Output of step goes to next step in same parallel process. No interprocess communication（進程間通信） to parent.
PARALLEL_COMBINED_WITH_CHILD - Parallel execution. Input of step comes from prior（先） step in same parallel process. No interprocess communication from child.
PARTITION_START
VARCHAR2(255)
Start partition of a range of accessed partitions:
number - Start partition has been identified by the SQL compiler（編譯）, and its partition number is given by number
KEY - Start partition will be identified at run time from partitioning key values
ROW REMOVE_LOCATION - Start partition (same as the stop partition) will be computed at run time from the location of each record being retrieved（檢索）. The record location（位置） is obtained（獲得） by a user or from a global index.
INVALID - Range of accessed partitions is empty
PARTITION_STOP
VARCHAR2(255)
Stop partition of a range of accessed partitions:
number - Stop partition has been identified by the SQL compiler, and its partition number is given by number
KEY - Stop partition will be identified at run time from partitioning key values
ROW REMOVE_LOCATION - Stop partition (same as the start partition) will be computed at run time from the location of each record being retrieved. The record location is obtained by a user or from a global index.
INVALID - Range of accessed partitions is empty
PARTITION_ID
NUMBER(38)
Step that has computed the pair of values of thePARTITION_START and PARTITION_STOP columns
OTHER
LONG
Other information that is specific to the execution step that a user might find useful (see the OTHER_TAG column)
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
DISTRIBUTION
VARCHAR2(30)
Method used to distribute rows from producer query servers to consumer query servers
See Also: Oracle Database Data Warehousing Guide for more information about consumer and producer query servers
CPU_COST
NUMBER(38)
CPU cost of the operation as estimated by the query optimizer's approach. The value of this column is proportional to the number of machine cycles required for the operation. For statements that use the rule-based approach, this column is NULL.
IO_COST
NUMBER(38)
I/O cost of the operation as estimated by the query optimizer's approach. The value of this column is proportional to the number of data blocks read by the operation. For statements that use the rule-based approach, this column is NULL.
TEMP_SPACE
NUMBER(38)
Temporary space (in bytes) used by the operation as estimated by the query optimizer's approach. For statements that use the rule-based approach, or for operations that do not use any temporary space, 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 query optimization. For statements that use the rule-based approach, this column is NULL.
QBLOCK_NAME
VARCHAR2(30)
Name of the query block (either system-generated or defined by the user with the QB_NAME hint)
