Vladimir Ciobanu da8f6981d4 server: reduce the number of backend dispatches ... Fixes https://github.com/hasura/graphql-engine-mono/issues/712 Main point of interest: the `Hasura.SQL.Backend` module. This PR creates an `Exists` type indexed by indexed type and packed constraint while hiding all of its complexity by not exporting the constructor. Existential constructors/types which are no longer (directly) existential: - [X] BackendSourceInfo :: BackendSourceInfo - [x] BackendSourceMetadata :: BackendSourceMetadata - [x] MOSourceObjId :: MetadatObjId - [x] SOSourceObj :: SchemaObjId - [x] RFDB :: RootField - [x] LQP :: LiveQueryPlan - [x] ExecutionStep :: ExecStepDB This PR also removes ALL usages of `Typeable.cast` from our codebase. We still need to derive `Typeable` in a few places in order to be able to derive `Data` in one place. I have not dug deeper to see why this is needed. GitOrigin-RevId: bb47e957192e4bb0af4c4116aee7bb92f7983445		2021-03-15 13:03:55 +00:00
..
Generator.hs	server: reduce the number of backend dispatches	2021-03-15 13:03:55 +00:00
Types.hs	Optimistic Metadata Locking	2021-02-19 02:40:23 +00:00