The DATE, DATETIME, and TIMESTAMP types are related. This section describes their characteristics, how they are similar, and how they differ. MySQL recognizes DATE, DATETIME, and TIMESTAMP values in several formats, described in Section 11.1.3, “Date and Time Literals”.For the DATE and DATETIME range descriptions, “ supported ” means that although earlier values might work, there is no ...

For exact-value numbers, ROUND() uses the “ round half away from zero ” or “ round toward nearest ” 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. (In other words, it is rounded away from zero.)

Many encryption and compression functions return strings for which the result might contain arbitrary byte values. If you want to store these results, use a column with a VARBINARY or BLOB binary string data type. This avoids potential problems with trailing space removal or character set conversion that would change data values, such as may occur if you use a nonbinary string data type (CHAR ...

GROUPING() permits multiple expression arguments. In this case, the GROUPING() return value represents a bitmask combined from the results for each expression, where the lowest-order bit corresponds to the result for the rightmost expression. For example, with three expression arguments, GROUPING(expr1, expr2, expr3) is evaluated like this:

These rules are applied for each operation, such that nested calculations imply the precision of each component. Hence, (14620 / 9432456) / (24250 / 9432456), resolves first to (0.0014) / (0.0026), with the final result having 8 decimal places (0.60288653). Because of these rules and the way they are applied, care should be taken to ensure that components and subcomponents of a calculation use ...

String-valued functions return NULL if the length of the result would be greater than the value of the max_allowed_packet system variable. See Section 7.1.1, “Configuring the Server”.. For functions that operate on string positions, the first position is numbered 1. For functions that take length arguments, noninteger arguments are rounded to the nearest integer.