We often need to compute datetimes based on year and month. This tiny function simplifies such queries:



set global log_bin_trust_function_creators=1;

create function yearmonth(d date) returns int

return 100*year(d)+month(d);

Then to find date values within the three-month period bounded by the first day of last month and the last day of next month, write ...



select d

from tbl

where yearmonth(d) between yearmonth(curdate()-interval 1 month) and yearmonth(curdate()+interval 1 month);