pg - PostgreSQL connector for Tarantool

Getting Started

Prerequisites

• Tarantool 1.6.5+ with header files (tarantool && tarantool-dev packages)
• PostgreSQL 8.1+ header files (libpq-dev package)

Installation

Clone repository and then build it using CMake:

git clone https://github.com/tarantool/pg.git
cd pg && cmake . -DCMAKE_BUILD_TYPE=RelWithDebugInfo
make
make install

You can also use LuaRocks:

luarocks install https://raw.githubusercontent.com/tarantool/pg/master/pg-scm-1.rockspec --local

See tarantool/rocks for LuaRocks configuration details.

Usage

local pg = require('pg')
local conn = pg.connect({host = localhost, user = 'user', pass = 'pass', db = 'db'})
local tuples = conn:execute("SELECT ? AS a, 'xx' AS b", 42))
conn:begin()
conn:execute("INSERT INTO test VALUES(1, 2, 3)")
conn:commit()

API Documentation

conn = pg:connect(opts = {})

Connect to a database.

Options:

• host - a hostname to connect
• port - a port numner to connect
• user - username
• pass or password - a password
• db - a database name
• connstring (mutual exclusive with host, port, user, pass, db) - PostgreSQL connection string
• raise = false - raise an exceptions instead of returning nil, reason in all API functions

Returns:

• connection ~= nil on success
• nil, reason on error if raise is false
• error(reason) on error if raise is true

conn:execute(statement, ...)

Execute a statement with arguments in the current transaction.

Returns:

• { { column1 = value, column2 = value }, ... } on success
• nil, reason on error if raise is false
• error(reason) on error if raise is true

Example:

tarantool> conn:execute("SELECT ? AS a, 'xx' AS b", 42)
---
- - a: 42
    b: xx
    ...

conn:begin()

Begin a transaction.

Returns: true

conn:commit()

Commit current transaction.

Returns: true

conn:rollback()

Rollback current transaction.

Returns: true

conn:ping()

Execute a dummy statement to check that connection is alive.

Returns:

• true on success
• false on failure

See Also

• Tests
• Tarantool
• Tarantool Rocks