annotate sql.urs @ 15:6ebc2ca594b7

Sql.insertIfMissing and deleteByKey (partly from Ron de Bruijn)
author Adam Chlipala <adam@chlipala.net>
date Sun, 11 Dec 2011 14:04:34 -0500
parents d05943db55e8
children 959583692166
rev   line source
adam@6 1 (** Common metaprogramming patterns for SQL syntax construction *)
adam@6 2
adam@6 3 val sqexps : env ::: {{Type}} -> fields ::: {Type} -> folder fields -> $(map sql_injectable fields)
adam@6 4 -> $fields -> $(map (sql_exp env [] []) fields)
adam@6 5 (* Convert a record of Ur values into a record of SQL expressions *)
adam@6 6
adam@6 7 val selector : tn :: Name -> fs ::: {Type} -> ofs ::: {Type} -> [fs ~ ofs]
adam@6 8 => folder fs -> $(map sql_injectable fs) -> $fs
adam@6 9 -> sql_exp [tn = ofs ++ fs] [] [] bool
adam@6 10 (* Build a boolean SQL expression expressing equality of some fields of a table
adam@6 11 * row with a record of Ur values *)
adam@13 12
adam@13 13 val joiner : tn1 :: Name -> tn2 :: Name -> fs ::: {Type} -> ofs1 ::: {Type} -> ofs2 ::: {Type}
adam@13 14 -> [[tn1] ~ [tn2]] => [fs ~ ofs1] => [fs ~ ofs2]
adam@13 15 => folder fs
adam@13 16 -> sql_exp [tn1 = ofs1 ++ fs, tn2 = ofs2 ++ fs] [] [] bool
adam@13 17 (* Declare equality of same-named columns from two tables. *)
adam@15 18
adam@15 19 val insertIfMissing : keyCols ::: {Type} -> otherCols ::: {Type} -> otherKeys ::: {{Unit}}
adam@15 20 -> [keyCols ~ otherCols] => [[Pkey] ~ otherKeys]
adam@15 21 => sql_table (keyCols ++ otherCols) ([Pkey = map (fn _ => ()) keyCols] ++ otherKeys)
adam@15 22 -> $(keyCols ++ otherCols)
adam@15 23 -> folder keyCols -> $(map sql_injectable keyCols)
adam@15 24 -> folder otherCols -> $(map sql_injectable otherCols)
adam@15 25 -> transaction bool
adam@15 26 (* Insert a row into an SQL table if its key isn't already present, returning [False] iff the key was already present *)
adam@15 27
adam@15 28 val deleteByKey : keyCols ::: {Type} -> otherCols ::: {Type} -> otherKeys ::: {{Unit}}
adam@15 29 -> [keyCols ~ otherCols] => [[Pkey] ~ otherKeys]
adam@15 30 => sql_table (keyCols ++ otherCols) ([Pkey = map (fn _ => ()) keyCols] ++ otherKeys)
adam@15 31 -> $keyCols -> folder keyCols -> $(map sql_injectable keyCols)
adam@15 32 -> transaction {}
adam@15 33 (* Delete a row from a table by matching its primary key against a given record. *)