Mercurial > urweb
diff lib/ur/basis.urs @ 1421:3dab4696d116
Subqueries may always return NULL
author | Adam Chlipala <adam@chlipala.net> |
---|---|
date | Thu, 03 Feb 2011 21:04:12 -0500 |
parents | 00b79f39be25 |
children | 541673c3161d |
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--- a/lib/ur/basis.urs Thu Feb 03 11:12:48 2011 -0500 +++ b/lib/ur/basis.urs Thu Feb 03 21:04:12 2011 -0500 @@ -529,9 +529,10 @@ -> sql_exp tables agg exps t -> sql_exp tables agg exps (option t) -val sql_subquery : tables ::: {{Type}} -> agg ::: {{Type}} -> exps ::: {Type} -> nm ::: Name -> t ::: Type +val sql_subquery : tables ::: {{Type}} -> agg ::: {{Type}} -> exps ::: {Type} -> nm ::: Name -> t ::: Type -> nt ::: Type + -> nullify t nt -> sql_query tables agg [] [nm = t] - -> sql_exp tables agg exps t + -> sql_exp tables agg exps nt (*** Executing queries *)