database - MySQL select/insert/update, does column order matter? -


In my mysql db, I have field id, name, email, age, city, phone

If I say that

do I speed 

  Contrary to

from the original order of code> 

  select phone, city, name, id, age,> columns: Not only a small For a simple query (only one example), select ID, name, email, age, city, phone to tableline // worry 100,000 rows and multiple / advanced questions And also for loops

No, it does not make any difference unless you select speed You can use the index to increase or just really select the column. When selecting, they will be returned to the order you have selected, you can also use the group to group the results of a particular column.

"It will not make any difference.

However, except for columns from the SELECT section it will have to run faster as it sends fewer data to the network."

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