Mantra official documentation

17-fast-crud-summary.md

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Red Entities fast CRUD summary

Here you have a fast reference to remember how to write typical CRUD sentences to work with the data of your applications.

Given this sample schema:

const sampleSchema = {
    entities: [
        {
            name : "users",
            fields: [
                { name : "mail", type : "string" },
                { name : "password", type : "string" },
                { name : "created", type : "datetime" }
            ],
            indexes: [ ["mail"], ["created"] ],
            restrictions: {
                unique: [ ["mail"] ]
            }
        }
    ]
}

const RedEntities = require("redentities")({
    provider: "mysql",
    host: "localhost",
    user: "myuser",
    password: "mypassword"
});

const db = RedEntities.Entities(sampleSchema);

, you can write the following basic CRUD operations for any of the providers supported by Red Entitities.

Select queries ( S() selector )

Select all fields of a single entity given its ID:

const userEntity = await db.users.S().SingleById( userId );

Select field name of a single entity given its ID:

const userEntity = await db.users.s("mail").SingleById( userId );

Get the number of users entities:

const usersCount = await db.users.S().C();

Or...

const usersCount = await db.users.S().Count();

Get an user given its mail:

const userEntity = await db.users.S().W("mail=?",mail).Single();

Check if an user given its mail exists:

const userExists = await db.users.S().W("mail=?",mail).Exists();

Iterate over all user entities:

await db.users.S().IA( await (userEntity) => {
    // Do something with userEntity
});

Get last user created according to created field:

const lastUserCreated = await db.users.S().OB('created').T(1).R();

Get older user created according to created field:

const olderUserCreated = await db.users.S().OB('created',false).T(1).R();

Get users entities paginated from position 10 and get 20:

const userEntities = await db.users.S().L(10,20).R();

Insert queries ( I() selector )

Insert a new user entity:

const newUserId = await db.users.I().V( { mail: 'mantrarocks@mantrajs.com', password: 'fooIlovePizza' } ).R();

Insert a number of users entities:

const newUsersId = await db.users.I().V( 
    [{ mail: 'mantrarocks@mantrajs.com', password: 'fooIlovePizza' },
     { mail: 'mantrarocks2@mantrajs.com', password: 'btcrocks' }] ).R();

Update queries ( S() selector )

Update mail field of an user given its ID:

await db.users.U().W('ID=?',userId).V( { mail: 'newmail@joo.com' }).R();

Delete queries ( D() selector )

Delete an user entity given its id:

await db.users.D().DeleteById( userId );

Delete an user given its mail:

await db.users.D().W("mail=?",userMailToDelete).R();