MySQL PERIOD_DIFF() Function

The MySQL PERIOD_DIFF() function returns the difference between two periods. The result will be in months. The parameters period1 and period2 must be formatted as either YYMM or YYYYMM, but do not have to be the same format as each other.

Syntax

PERIOD_DIFF(period1, period2)

Parameters

Return Value

Returns the difference between two periods.

Example 1:

The example below shows the usage of PERIOD_DIFF() function.

mysql> SELECT PERIOD_DIFF(201805, 201801);
Result: 4

mysql> SELECT PERIOD_DIFF(201801, 201805);
Result: -4

mysql> SELECT PERIOD_DIFF(201805, 1901);
Result: -8

mysql> SELECT PERIOD_DIFF(1901, 201805);
Result: 8

mysql> SELECT PERIOD_DIFF(1706, 1901);
Result: -19

mysql> SELECT PERIOD_DIFF(1901, 1706);
Result: 19

Example 2:

Consider a database table called Sample with the following records:

To calculate the difference between periods specified by values of column Period1 and column Period2, the following query can be used:

SELECT *, PERIOD_DIFF(Period1, Period2) AS PERIOD_DIFF_Value FROM Sample;

This will produce the result as shown below: