Lua Query Builder

LuaQuB is a small query builder module for Lua. I am building this because I'm tired of typing similar queries over and over as strings.

Requirements

The module will work perfectly with Lua v5.x

Usage

Save the LuaQuB.lua file (in root directory) to a folder listed under Lua's package.path or package.cpath variable. Call the module in your program by using require as follows:

local Builder = require "LuaQuB"

Create an object by using .new() method of Builder module. This object will be used for bulding the query.

local object = Builder.new()
object:select( "id, date, time, message, t2.col1, t2.col2" )
object:from( "tbl1, tbl2 AS t2" )
object:where( "tbl1.id = t2.remote_id" )
object:where( "LENGTH(message) < 255" )
object:limit( 30, 10 )		-- The second argument is offset

To get the compiled query in string format, just call tostring passing the object as parameter.

print( tostring(object) )

which will give you the following output

SELECT id,
	date,
	time,
	message,
	t2.col1,
	t2.col2
FROM tbl1,
	tbl2 AS t2
WHERE tbl1.id = t2.remote_id
	AND LENGTH(message) < 255
LIMIT 30
OFFSET 10

Building

LuaQuB can build queries for SELECT, UPDATE, INSERT and DELETE commands. The output is for MySQL. There is no plan on increasing support for other database engines.

Examples

Short examples for each of the four supported commands and their various variations have been added under the tests/ directory.

Not supported

The module does not check whether your input was properly escaped or not. It assumes that your input will be accordingly given.