X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=src%2FTSN%2FDatabase.hs;fp=src%2FTSN%2FDatabase.hs;h=935033066ae65d416fde566cf1f1b0697637b7fd;hb=c5d61081ad0d95950ca06761978d240632c44510;hp=0000000000000000000000000000000000000000;hpb=7a5034bbe4feb8625b3a6c534f07427ecf848ad8;p=dead%2Fhtsn-import.git

diff --git a/src/TSN/Database.hs b/src/TSN/Database.hs
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+++ b/src/TSN/Database.hs
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+-- | Standalone database functions for dealing with Groundhog types.
+--
+module TSN.Database ( insert_or_select )
+where
+
+import Database.Groundhog ( AutoKey, insertByAll )
+import Database.Groundhog.Core ( PersistBackend, PersistEntity )
+
+
+-- | Attempt to insert the given object returning its new primary
+--   key. If any unique constraints would be violated, instead return
+--   the primary key of the existing record that caused the collision.
+insert_or_select :: (PersistBackend m, PersistEntity a)
+                 => a
+                 -> m (AutoKey a)
+insert_or_select x = do
+  tmp <- insertByAll x
+  return $ (either id id) tmp