paulrzcz/persistent-odbc

uses persistent connecting via hdbc odbc

persistent-odbc

Uses the Persistent package and HDBC-odbc to access databases via ODBC.

Thanks to Dmitry Olshansky at https://github.com/odr/persistent-odbc/ for doing the initial hookup to hdbc-odbc.

Supports Postgres, MySql, MS Sql Server, Oracle, DB2, and SQLite.

see TestODBC.hs for usage and tests.

##How to get started using cabal >= 1.18 git clone https://github.com/gbwey/persistent-odbc cd persistent-odbc cabal sandbox delete cabal sandbox init cabal install --only-dependencies --flags="tester" cabal configure --flags="tester" cabal repl

:load TestODBC.hs  (also need to define the appropriate odbc system dsn below and then run the command)

e.g. for postgresql
    1. define the system odbc dsn pg_test
    2. :main p  

DBMS	ODBC System Dsn	Command
Postgresql	dsn=pg_test	:main p
MySQL	dsn=mysql_test	:main m
DB2	dsn=db2_test	:main d
Ms Sql Server >= 2012	dsn=mssql_test; Trusted_Authentication=True;	:main s
Ms Sql Server pre 2012	dsn=mssql_test; Trusted_Authentication=True;	:main so
Oracle pre 12c	dsn=oracle_test	:main o
Oracle >= 12c	dsn=oracle_test	:main on
Sqlite	dsn=sqlite_test	:main q

####Limit and Offset in Ms Sql Server and Oracle MSSQL True for MS Sql Server 2012 which has limit and offset support (esqueleto as well). MSSQL False for MS Sql Server pre 2012 only supports limit using Persistent's select* operations. (select top n ...).

Oracle True for Oracle >=12c which has limit and offset support (esqueleto as well). Oracle False for Oracle <12c where there is no limit and offset support.

####Ms Sql Server and blobs Blobs don't support nulls (both insert and select) in this version of persistent-odbc (also doesn't work in hdbc-odbc). You may have problems with blobs and latest 2012 odbc driver.

####Ms Sql Server and deleteCascadeWhere Can cause segfault in Ms Sql Server.

####Oracle and nulls Treats empty string as a null (oracle issue).

####Oracle and sorting blobs Cannot sort on a blob field (oracle issue).

####DB2 and blobs Blobs don't support nulls (both insert and select) in this version of persistent-odbc (also doesn't work in hdbc-odbc). Select returns the blob values as unpacked strings at the moment (if there is interest in getting this fixed let me know).