SQL/MP Query Guide

Analyzing Query Performance
HP NonStop SQL/MP Query Guide—524488-003
6-74
EXPLAIN Plan for INSERT
The total cost of the query is 1.
The plan contains the following information:
•
The lock granularity is record (row):
Access type : Record locks, stable access
•
The type of delete is a cursor delete.
EXPLAIN Plan for INSERT
The EXPLAIN plan shows an INSERT operation.
The query inserts data into the ordtwo table, as follows:
EXPLAIN
INSERT INTO ordtwo VALUES (100) ;
The total cost of the query is 1.
Example 6-45 on page 6-75 shows the EXPLAIN plan for the query.
Example 6-44. EXPLAIN Plan for Cursor DELETE
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Query plan 1
SQL request : Delete
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---------------------------------------------------------------------------
Plan step 1
---------------------------------------------------------------------------
Operation 1.0 : Scan
Table : \SQL1.$DATA8.PERSNL.EMPLOYEE
with correlation name EMPLOYEE
Access type : Record locks, stable access
Lock mode : Chosen by the system
Column processing : Requires retrieval of 0 out of 6 columns
Access path 1 : Alternate \SQL1.$DATA8.PERSNL.XEMPDEPT, index
only
SBB for reads : Virtual
Begin key pred. : DEPTNUM = 1500
End key pred. : DEPTNUM = 1500
Index selectivity : Expect to examine 9.0909% of rows from index
Index pred. : None
Base table pred. : None
Type of Delete : Cursor
Executor pred. : None
Table selectivity : Expect to select 9.0909% of rows from table
Expected row count: 11 rows after the scan
Operation cost : 1
Total cost : 1