SQL/MX 2.x Query Guide (G06.24+, H06.03+)

Forcing Execution Plans

HP NonStop SQL/MX Query Guide—523728-003

5-5

Translating the Operator Tree to Text Format

You must translate the operator tree into a text format. The text format used to

represent the tree to the CONTROL QUERY SHAPE statement is written in a LISP-like

format. (LISP stands for list processor, a high-level programming language.)

Using SHOWSHAPE and SET SHOWSHAPE to View the Text

Format

If you are using MXCI to execute your queries, you can use the SHOWSHAPE and

SET SHOWSHAPE commands to view the text format for the CONTROL QUERY

SHAPE statement. The SHOWSHAPE command simply shows the text format for the

shape of the statement you execute; it does not show the Explain output.

>>SHOWSHAPE SELECT last_name, first_name, manager,

+>employee.deptnum, job.jobcode FROM dept, employee, job

+>WHERE dept.deptnum=3100 AND employee.deptnum=3100 AND

+>job.jobcode=300;

control query shape

hybrid_hash_join(hybrid_hash_join(partition_access(

scan(path 'SAMDBCAT.PERSNL.EMPLOYEE',

vst601.vsd