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create table foo (qtr text) select '1Q2013' qtr;
Records: 1 Duplicates: 0 Warnings: 0
select date(concat(substring_index(qtr,'Q',-1),'-01-01')) + interval substring_index(qtr,'Q',1)*3 month - interval 1 day from foo
| date(concat(substring_index(qtr,'Q',-1),'-01-01')) + interval substring_index(qtr,'Q',1)*3 month - interval 1 day |
|---|
| 2013-03-31 |