6. Troubleshooting Ingres : Resource and Maintenance Problems : Tools for Identifying Operating System Problems : Diagnose Poor Performance Due to Insufficient System Resources : VMS:
 
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VMS:
stop process/id = pid
where pid is the process ID of the query.
The command format “stop proc” must be used only as a last resort. Use of this option can cause more problems than it solves.
b. Issue the command set gep.
Rerun the query. This outputs a query execution plan.
Alternatively, start an SQL window on the database in VDBA and click the Display Query Execution Plan button to graphically display the query plan.
Interrupting a query requires some time because Ingres is optimized to commit rather than back out of transactions. It takes at least as long to back out of a transaction as to process the transaction normally. The transaction must be fully backed out before sessions can resume and locks are freed.
4. It is useful to note whether the query runs differently when called from other Ingres tools. For example, try issuing the same query from Interactive SQL, and Embedded SQL
5. Determine if you can access all of the data in the tables in all components of the query.
a. From the Terminal Monitor type:
select count(*) from tablename
This verifies that Ingres can sequentially access every row in the table and indicates that other access paths (secondary indexes, hash pointers, B-Tree page pointers, and so on) can cause the problem. Queries using restrictive where clauses probably are using these secondary access methods.
b. Check for permits that apply to this data by typing the following command from the Terminal Monitor:
help permit tablename