minute(param) - Returns the minute component of the string/timestamp/interval
param can be one of:
1. A string in the format of 'yyyy-MM-dd HH:mm:ss' or 'HH:mm:ss'.
2. A timestamp value
3. A day-time interval valueExample:
   > SELECT minute('2009-07-30 12:58:59') FROM src LIMIT 1;
  58
  > SELECT minute('12:58:59') FROM src LIMIT 1;
  58