MySQL Decimal Clarification
When using decimal in MySQL, does a value of (5,3)
make it so the max number is 99.999
? If not how do I specify that? My number is for currency so I need to use decimal, but it should n开发者_高级运维ot go over 99 and it must have 3 decimal places.
decimal (5,3)
is the standard SQL way to define a field with a range of -99.999 .. 99.999
.
Note that with MySQL, if you attempt to insert a value that is out of range, MySQL will automatically truncate the value to the nearest boundary value (in this case, either 99.999 or -99.999) without throwing an error.
Added
In this case, there will be a maximum of 5
digits of data stored, with exactly 3
digits to the right of the decimal point. If you insert a number like 1.23
it will be stored as 1.230
; likewise 1
will be stored as 1.000
. If you insert 12.3456
it will be rounded up to 12.346
; if you insert 12.0001
it will be rounded down to 12.000
.
When the column is returned to your program, the exact representation will depend upon how your database API maps a decimal data type. If it maps to an integer, you'll lose the decimal fraction; if it maps to a floating point number (float, double), you may lose precision; if it maps to a Decimal (C#/Java) then you'll get an exact representation, as long as your value is within the bounds of the datatype.
The method you specified should work. I don't see any problems with it.
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