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Compare select * and select all fields to write speed examples
Compare select * and select all fields to write speed examples
From a very early age, I heard the teacher say that select * from table is much slower than select a,b,c,d from table. Never tested in 3 years. I'll take a test today if I have nothing to do. I don't know if something unexpected happens. I'll be shocked if I take the test.
Of course the following is purely a test and has not been applied to actual projects. If you have any comments or suggestions, please let me know.
| Number of times | *No. query | Field query |
| First Time |
|
|
| Second Time | 
|
|
| the third time | 
|
|
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