postgresql - Postgres Tuning -

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What are the effective ways of writing fast questions in postgres especially? Please do not usually include good database practices (such as using indexed or generalization) I am looking for signals such as derived tables have to work faster than subcategories or using Python string functions pgsql string functions Seems faster than Ideally, this list will include examples and advice from the real world.

Thank you.

Ensuring vacuum from time to time The current auto-out system works very well in most cases, But from time to time, full manual vaccum can still be useful to run (in our case this happens almost once per year).

Only indexes are used reliably if the data is available for the table, make sure that a vacuum-analysis table is run after any major change (several tons of inverse / deletion) , To ensure that the index is selected properly.

The default postgrace configuration is relatively flexible for the system. Minor processing and slow discs If your system has a faster disk (possibly), a faster CPU (maybe), or too much RAM (almost certainly) , Then make sure to tune the different parameters based on that. The main thing is to increase buffer sizes, but if you have a very fast disk (especially SSD), then looking for time would be a good idea to reduce cost estimates.

I also experience some of the slowest speed in very complex questions, but it is difficult to generalize them. Typically this query helps to be more clear than necessary in DB with a more sophisticated query optimizer (for example, Oracle or DB2).


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