MySQL 8.0: Removing support for old temporal datatypes
MySQL 5.6 introduced the fractional second precision for temporal data types – TIME, DATETIME, and TIMESTAMP, with up to microseconds (6 digits) precision. Along with providing fractional second precision, the new implementation for temporals is disk efficient.
What is an “Old Temporal”?
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Source: MySQL 8.0: Removing support for old temporal datatypes
