From Zlatko Matic:
MightyQuery is a single user SQL database management software working with data stored as comma separated values (.csv, .txt) in plain, flat, textual files. It is serverless, self-contained, simple and effective SQL DBMS for querying CSV files. In contrast to most database systems, MightyQuery does not require neither server installation, neither external libraries. Though there are other database solutions that can process single textual file, MightyQuery is distinguished from them by its SQL engine, by which you can query and modify CSV tables with power that is normally reserved for huge enterprize-level SQL engines.
MightyQuery is suitable for managing simple personal databases, in cases where installing and managing complicated SQL servers is overkill for you. To enable processing of external data, Mighty Query contains importing utility, supporting wide range of SQL database servers, such as PostgreSQL, Interbase, Firebird, MSSQL, Sybase, SQLite, Oracle, ado, and ASA.