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This maybe an easy one but i couldn't get answer. I need to select float value from table
example table :-
value
10.2
4.5
4.6
4.06
my query
SELECT * FROM table where value = '4.6'
returns empty result set
how can i solve this !
616
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) is displayed as -999.9999 .
MySQL uses four bytes to store a FLOAT value. DOUBLE is a double precision floating point number. MySQL uses eight bytes to store a DOUBLE value. MySQL treats DOUBLE as a synonym for DOUBLE PRECISION (a non-standard extension).
You can also try query
SELECT * FROM table WHERE value LIKE 4.6;
Generally, you should never check equality with floats (unless, potentially, you have the same object). Internally, it is represented with more precision, even if it isn't showing it to you by the time it outputs to the screen. This basic tenet holds true for computing in general.
There are a dozens of schemes for doing this, but here is a simple one, which should make sense:
SELECT * FROM table where value BETWEEN 4.599 AND 4.601
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