float(2,2)
means "use two digits, of which two are used after the decimal point".
Hence, you can go from -0.99 to 0.99. You can't insert 10 into this column, you'd need atleast two digits before the comma (so float(4,2) or float(2,0)).
MySQL permits a nonstandard syntax: FLOAT(M,D) or REAL(M,D) or DOUBLE PRECISION(M,D). Here, “(M,D)” means than values can be stored with up to M digits in total, of which D digits may be after the decimal point. For example, a column defined as FLOAT(7,4) will look like -999.9999 when displayed. MySQL performs rounding when storing values, so if you insert 999.00009 into a FLOAT(7,4) column, the approximate result is 999.0001.
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