CODEWITHSUNDEEP
postgresql
pree
pree

Reputation: 2357

query execution time

I am wondering if someone can help me understand the following query execution behavior:

I have two similar tables and table2 consists of 5000000 records.

Query: INSERT INTO table1 SELECT * FROM table2. Execution Time: A ms.

Query: INSERT INTO table1 SELECT * FROM table2. Execution Time: B ms.

Sometimes B >> A (B is very larger than A). Both queries are same and run twice. What could be the reason that the same query is taking very long sometime?

Thanks a lot!

Upvotes: 0

Views: 773

Answers (1)

francs
francs

Reputation: 9189

Can you do the test, and past all the information including the execcution time , table ddl out ? What's more ,you can use "explain analyze" before your statements to see if there any differentia between the two situation.

Upvotes: 1

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