Mercurial > urweb
annotate tests/subquery.ur @ 1931:1a04b1edded2
Fix regression in http.c for long-polling connections; add lazy initialization of database connections, to avoid the overhead in handlers that don't use SQL
| author | Adam Chlipala <adam@chlipala.net> |
|---|---|
| date | Wed, 11 Dec 2013 14:57:54 -0500 |
| parents | 9c82548c97e9 |
| children |
| rev | line source |
|---|---|
| adamc@1191 | 1 table t : { A : int, B : int, C : int } |
| adamc@1191 | 2 |
| adamc@1191 | 3 fun main () = |
| adamc@1191 | 4 v <- queryX1 (SELECT t.A, t.C |
| adamc@1191 | 5 FROM t |
| adamc@1191 | 6 WHERE t.B = (SELECT MAX(U.B) AS M |
| adamc@1191 | 7 FROM t AS U |
| adamc@1191 | 8 WHERE U.A = t.A)) |
| adamc@1192 | 9 (fn r => <xml>{[r.A]},{[r.C]};</xml>); |
| adamc@1192 | 10 v' <- queryX1 (SELECT t.A, t.C |
| adamc@1192 | 11 FROM (SELECT t.A AS A, MAX(t.B) AS B |
| adamc@1192 | 12 FROM t |
| adamc@1192 | 13 GROUP BY t.A) AS Maxes |
| adamc@1192 | 14 JOIN t ON t.A = Maxes.A AND t.B = Maxes.B) |
| adamc@1192 | 15 (fn r => <xml>{[r.A]},{[r.C]};</xml>); |
| adamc@1192 | 16 return <xml><body> |
| adamc@1192 | 17 {v}<br/> |
| adamc@1192 | 18 {v'} |
| adamc@1192 | 19 </body></xml> |