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Old 11-18-05, 17:03
chas_dba chas_dba is offline
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Unhappy Multi_table join

We have a db2 schema with 50 odd tables . of which
One set of tables (TypA) are indexed and cluster with C1 column data. Similarily we have another set (TypB) with clustering of A1.
There is another big table with TypC with index I1.. not directly related to the other two sets.

When involved in a cursor of multi_table join, the performance is bad
TypC table is driving the I/O waits crazy, i think its because of the Random access for the records.

This is forcing us to do the query in two parts, one join and one simple select on TypC. We tried to use order by the column which is used to join TypC.

Any suggestions for getting the query in one join with resonable performance is greatly appreciated.
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Old 11-18-05, 22:08
Marcus_A Marcus_A is offline
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You need to post the table and index DDL, and the SQL query with the join.
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