PLAN_TABLE_DATA

PLAN_TABLE_DATA displays the plan information collected by EXPLAIN PLAN. Different from the PLAN_TABLE view, the system catalog PLAN_TABLE_DATA stores the plan information collected by all sessions and users.

Table 1 PLAN_TABLE columns

Name

Type

Description

session_id

text

Session that inserts the data. Its value consists of a service thread start timestamp and a service thread ID. Values are constrained by NOT NULL.

user_id

oid

User who inserts the data. Values are constrained by NOT NULL.

statement_id

varchar2(30)

Query tag specified by a user

plan_id

bigint

ID of a plan to be queried

id

int

Node ID in a plan

operation

varchar2(30)

Operation description

options

varchar2(255)

Operation parameters

object_name

name

Name of an operated object. It is defined by users.

object_type

varchar2(30)

Object type

object_owner

name

User-defined schema to which an object belongs

projection

varchar2(4000)

Returned column information

Note

  • PLAN_TABLE_DATA records data of all users and sessions on the current node. Only administrators can access all the data. Common users can view only their own data in the PLAN_TABLE view.

  • Data of inactive (exited) sessions is cleaned from PLAN_TABLE_DATA by gs_clean after being stored in this system catalog for a certain period of time (5 minutes by default). You can also manually run gs_clean -C to delete inactive session data from the table..

  • Data is automatically inserted into PLAN_TABLE_DATA after EXPLAIN PLAN is executed. Therefore, do not manually insert data into or update data in PLAN_TABLE_DATA. Otherwise, data in PLAN_TABLE_DATA may be disordered. To delete data from PLAN_TABLE_DATA, you are advised to use the PLAN_TABLE view.

  • Information in the statement_id, object_name, object_owner, and projection columns is stored in letter cases specified by users and information in other columns is stored in uppercase.