raw_sqlite3

The library provides a NIF interface to sqlite3.

The motivation behind the library is to have a low-level wrapper which exposes as much as of SQLite C API as possible, excluding anything that is outdated, dangerous, or just makes little or no sense to use in Erlang code.

While it is believed to be safe to use (including automatic object de-allocation), it might still be possible to crash the VM because there is no built-in validity checks for passed parameters. So use with caution!

Hopefully, other libraries may utilise raw_sqlite3 to build a safer, higher-level interface.

As opposed to esqlite3 the NIF does not spawn any extra OS threads, since most of the NIF functions are marked as IO-heavy to run on dirty schedulers. While it works fine most of the time, some edge cases are not impossible.

Interface

The sqlite3_nif module is assumed as the main entry point for the library. It provides wrappers for the every SQLite C API function, except:

• Deprecated functions;
• Potentially dangerous, global state mutating functions, such as sqlite3_config;
• Functions which require a function pointer;
• sqlite3_bind_* functions which are replaced by single sqlite3_bind/2;
• sqlite3_column_* functions which are merged into sqlite3_step/1;
• sqlite3_mutex_* functions which make no sense in Erlang code;
• API related to creating of user functions;
• Unicode variants of the C API (only UTF-8 version are allowed);
• Memory managing functions;
• _vfs_* functions;
• ...

Most of the exposed functions follow the C API to the letter so the official documentation should be considered as the primary source of information, while the C API introduction should be read as a "getting started guide".

File include/sqlite3_nif.hrl defines macros for C constants.

The raw_sqlite3 module contains a few convenience and utility functions to convert between C constants and Erlang atoms, as well as human-readable error messages.

Build

$ rebar3 compile

Test

$ rebar3 eunit