How to know whether I use analyze or DBMS_STATS

Automatic statistics gathering should be sufficient for most of the cases. And automatic statistics gathering is done by default during an overnight batch window. In order to know more about automatic statistics gathering just have a look at Analyze and collecting Statistics on Tables Schemas Database Index and About STATISTICS_LEVEL parameter in Oracle

In most cases automatic statistics gather is sufficient but still you may need to gather manually statistics if you do huge insert or update or delete on the table. You might know we can gather statistics by two ways.

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