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Why does MySQL round floats way more than?
The emphasis here lies on approximate. If you need to store exactvalues, you should really use the DECIMALdata type. For FLOAT, MySQL uses the IEEE standard 754 for binary floating point arithmetic to “compress” any fraction of a number into 4 bytes (or 8, for DOUBLE).
How is the rounding done in MySQL 5.7?
(In other words, it is rounded away from zero.) A value with a fractional part less than .5 is rounded down to the next integer if positive or up to the next integer if negative. (In other words, it is rounded toward zero.) For approximate-value numbers, the result depends on the C library.
What’s the approximate value of a float in MySQL?
MySQL performs rounding when storing values, so if you insert 999.00009 into a FLOAT (7,4) column, the approximate result is 999.0001 . Because floating-point values are approximate and not stored as exact values, attempts to treat them as exact in comparisons may lead to problems.
What’s the round half up rule in MySQL?
The ROUND() function rounds differently depending on whether its argument is exact or approximate: For exact-value numbers, ROUND() uses the “round half up” rule: A value with a fractional part of .5 or greater is rounded up to the next integer if positive or down to the next integer if negative.
How to use the round function in MySQL?
MySQL ROUND() Function 1 Definition and Usage. The ROUND () function rounds a number to a specified number of decimal places. TRUNCATE ()functions. 2 Syntax 3 Parameter Values. The number of decimal places to round numberto. 4 Technical Details. From MySQL 4.0 5 More Examples. SELECT ROUND (345.156,
How are floating point numbers formatted in MySQL?
You are relying on the user interface to format the floating point numbers. The interface you are using is using two characters rather than more. After all, there is no information on the “right” number to show. You can convince the interface to show the right number by formatting the number as a string or as a decimal. For instance:
Why do we use float and doubletypes in MySQL?
The FLOATand DOUBLEtypes represent approximate numericdata values. MySQL uses four bytes for single-precision values .. The emphasis here lies on approximate. If you need to store exactvalues, you should really use the DECIMALdata type.