ng-tql
v0.2.1
Published
A domain specific language that extends SQL and allows visual metaprogramming
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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.