Query Abstraction Layer
QAL is an open source development project that aims to create a collection of libraries for mixing, moving, merging, substituting and transforming data; also in some cases, such as MongoDB, schemas.
Sources and destinations include different database backends, file formats like .csv
, XML and spreadsheets. Even untidy HTML web pages can be used as both a source and destination.
For :Category:Relational database management systems|SQL/RDBMS backends, it has a database abstraction layer that supports basic connectivity to Postgres, MySQL / MariaDB, DB2, Oracle and MS SQL Server. It uses XML formats for representation of queries, transformation and merging, making it all processable by scripts.
With regards to SQL, QAL uses a subset of SQL features and data types, which while obviously not complete however is sufficient for most usages. It is however easy to instead use backend-specific SQL when the queries do not have to be backend-agnostic.
It is currently distributed as a Python Library and a Debian package file.
It is related to the Optimal BPM project. The Optimal BPM SourceForge project used to be DAL/QAL.