ng-tql

TQL

A domain specific language that extends SQL and allows visual metaprogramming

TQL is a small language that extends SQL and integrates with ng-sql-parser and query-wizard (that will still be open-sourced). The language has support to a small set of type-inference of literal types and a small type-checker. It receives TQL, processes it by GUI and generates valid SQL as output. Please note that this repository contains only the grammar definitions and the source for TQL, not the integration per se (at least not for now). TQL was built to make easy the integration between the front-end user and TOTVS Protheus ERP.

Type System

TQL has a small type-system and an inference model. It is able to deduce the type of every expression placed (all expressions are literals). All type declarations are optional.

Declare Val: Int
Declare Name: VarChar
Declare When: Date
Declare Age: Nat
Declare Trigger: Bool
Declare Table: Symbol
Declare Id: Char(32)
Declare Limit: Range(10, 100)
Declare Price: Double

Default Values

Use := to create default values, such as:

Declare Age: Nat := 18

Pictures

Pictures are made to tell how to display the data (on Protheus and on Query Wizard).

Declare Price: Double Picture '99.99' := 13.87

Range Types

Range types allow you to restrict data in ranges

Declare Age: Range(18, 60) := 10
Declare CPF: Char(11)

DateTime

You can use formats like:

Declare BirthDay := 4 Dec 1996
Declare EventTime := 7 Nov 2016 13:45

Descriptions

Specify information about the field within { and }.

Declare Age: Nat Picture '99' := 18 { The user age to search }

Usage

Install

• Yarn: yarn add ng-tql
• npm: npm install ng-tql

Compile from sources

Using Yarn:

yarn
yarn compile
yarn test

Using npm:

npm install
npm run compile
npm test

Using with ES6

import { parse } from 'ng-tql';
 
try {
    console.log(parse('Declare Age: Nat := 18'));
} catch (e) {
    console.log(e);
}

Credits

TQL is written with PegJS by Marcelo Camargo and open-source under MIT License.