MySQL 5.6 Reference Manual Including MySQL NDB Cluster 7.3-7.4 Reference Guide

11.2.7 Fractional Seconds in Time Values

MySQL 5.6 has fractional seconds support for TIME, DATETIME, and TIMESTAMP values, with up to microseconds (6 digits) precision:

In some cases, previously accepted syntax may produce different results. The following items indicate where existing code may need to be changed to avoid problems: