sql - MySQL query performance -

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i have following table structure:

event_id(int)    event_name(varchar)    event_date(datetime)    event_owner(int)

i need add field event_comments should text field or big varchar.

i have 2 places query table, 1 on page lists events (in page not need display event_comments field).

and page loads details specific events, need display event_comments field on.

should create table event_id , event_comments event? or should add field on current table?

in other words, i'm asking is, if have text field in table, don't select it, affect performance of queries table?

adding field table makes larger.

this means that:

  • table scans take more time
  • less records fit page , hence cache, increasing risk of cache misses

selecting field join, however, take more time.

so adding field table make queries don't select run slower, , select run faster.


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