Problem

String concatenation is slowing down a query:

date(extract(YEAR FROM m.taken)||'-1-1') d1,
date(extract(YEAR FROM m.taken)||'-1-31') d2

This is realized in code as part of a string, which follows (where the p_ variables are integers):

date(extract(YEAR FROM m.taken)||''-'||p_month1||'-'||p_day1||''') d1,
date(extract(YEAR FROM m.taken)||''-'||p_month2||'-'||p_day2||''') d2

This part of the query runs in 3.2 seconds with the dates, and 1.5 seconds without, leading me to believe there is ample room for improvement.

Question

What is a better way to create the date (presumably without concatenation)?

Many thanks!