annotate tests/query.ur @ 1168:69f1d39d3f2d
Use COALESCE to hide NULL results of aggregate functions; fix bug with improper ordering of query result columns
| author |
Adam Chlipala <adamc@hcoop.net> |
| date |
Thu, 25 Feb 2010 14:55:35 -0500 |
| parents |
5f9b9972e6b8 |
| children |
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| rev |
line source |
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adamc@253
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1 table t1 : {A : int, B : string, C : float, D : bool}
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adamc@243
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2 table t2 : {A : float, D : int}
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adamc@243
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3
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adamc@243
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4 datatype list a = Nil | Cons of a * list a
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adamc@243
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5
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adamc@254
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6 val q1 = (SELECT * FROM t1)
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adamc@253
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7
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adamc@253
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8 val r1 : transaction (list {A : int, B : string, C : float, D : bool}) =
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adamc@748
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9 query q1
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adamc@748
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10 (fn fs acc => return (Cons (fs.T1, acc)))
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adamc@748
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11 Nil
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adamc@243
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12
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adamc@249
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13 val r2 : transaction string =
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adamc@748
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14 ls <- r1;
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adamc@748
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15 return (case ls of
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adamc@748
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16 Nil => "Problem"
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adamc@748
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17 | Cons ({B = b, ...}, _) => b)
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adamc@249
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18
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adamc@748
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19 fun main () : transaction page =
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adamc@748
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20 s <- r2;
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adamc@748
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21 return <xml><body>
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adamc@748
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22 {cdata s}
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adamc@748
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23 </body></xml>
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