(WIP) A simple ORM for poets
Provides a safe & fluent interface for writing SQL queries.

Key features

• Fluent Interface (Method chaining)
• Powered by Nim's Macros System 👑
• Async Pool with Treeform's PG library
• Built-in Validation using String-based Filters
• Pluralize Models Support (English only)

Examples

Create a new model using macros:

import std/times
import enimsql

export enimsql

model "User":
    name: string
    email: string
    country: string
    city: string
    password: string
    created_at: DateTime
    updated_at: DateTime

Queries

• Select Statements
• Where Clauses
• Update Statements

Select Statements

You may not always want to select all columns from a database table. Using the select proc, you can create a custom SELECT clause by specifying column names you want to include in your results. select proc is accept a parameter of type varargs[string].

# Retrieve all records from `users` table and return only `name`, `email` and `country`
User.select("name", "email", "country").exec()

The selectDistinct proc allows you to force the query to return distinct results.

User.selectDistinct()

If you already have a query builder instance and you wish to add a column to its existing SELECT clause, you may use the addSelect proc:

var query = User.select("name")
let users = query.addSelect("email").exec()

Where Clause(s)

You may use the query builder's where proc to add WHERE clauses to the query. The most basic call to the where proc requires a varargs of KeyOperatorValue tuple with three arguments.

1. The first argument is the name of the column.
2. The second argument is an operator, which can be any of the database's supported operators.
3. The third argument is the value to compare against the column's value.

User.where(("email", EQ, "john.doe@example.com"))

When chaining together calls to the query builder's where procedure, the WHERE clauses will be joined together using the AND operator. Alternatively, since where proc accepts a varargs of KeyOperatorValue tuple, you can call where procedure and provide multiple KeyOperatorValue tuple.

User.where(
    ("email", NEQ, "john.doe@example.com"),
    ("city", EQ, "Milan")
)

The example above will produce the following SQL:

SELECT * FROM users
        WHERE email <> 'john.doe@example.com',
              city = 'Milan'

However, you may use the orWhere proc to join a clause to the query using the OR operator.

User.where(
        ("email", NEQ, "john.doe@example.com"),
        ("city", EQ, "Milan"))
     .orWhere(
        ("email", NEQ, "john.doe@example.com"),
        ("city", EQ "Torino"))

The example above will produce the following SQL:

SELECT * FROM users
         WHERE
            email <> 'john.doe@example.com' AND city = 'Milan'
            OR (
                email <> 'john.doe@example.com' AND city = 'Torino'
            )

Where Not Clauses

The whereNot and orWhereNot procs may be used to negate a given group of query constraints. For example, the following query excludes products that are on clearance or which have a price that is less than ten:

User.whereNot()

Update Statements

In addition to inserting records into the database, the query builder can also update existing records using the update proc. The update proc is a safe way for updating records because it requires a WHERE clause. To update all records in a table with same values use updateAll.

User.update(("email", "new.john.doe@example.com"))
    .where(("email", EQ, "john.doe@example.com"))
    .exec()

User.updateAll(("updated_at", now())).exec()

Joins

The query builder may also be used to add JOIN clauses to your queries. To perform a basic INNER JOIN, you may use the join procedure on a query builder instance.

import ./order, ./contacts

let users = User.join(Contact)

Roadmap

• Do the do

❤ Contributions

Help with ideas, bugfixing, contribute with code or donate via PayPal address 🥰

👑 Discover Nim language

What's Nim? Nim is a statically typed compiled systems programming language. It combines successful concepts from mature languages like Python, Ada and Modula. Find out more about Nim language

Why Nim? Performance, fast compilation and C-like freedom. We want to keep code clean, readable, concise, and close to our intention. Also a very good language to learn in 2022.

🎩 License

Enimsql is Open Source Software released under MIT license. Developed by Humans from OpenPeep.
Copyright © 2022 OpenPeep & Contributors — All rights reserved.