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Knex Cheat Sheet

Lâm
・2 min read

[Migrations] Setting up

Create knexfile.js

./node_modules/.bin/knex init
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Create a migration

knex migrate:make migration_name
knex migrate:make migration_name --env production
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Run migrations

knex migrate:latest
knex migrate:latest --env production
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Rollback

knex migrate:rollback
knex migrate:rollback --env production
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See: Migrations

[Modifying] Delete

knex('users')
  .where({ id: 2 })
  .del()
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See: Delete

[Modifying] Update

knex('users')
  .where({ id: 2 })
  .update({ name: 'Homer' })
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See: Update

[Modifying] Insert

knex('users')
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Insert one

  .insert({ name: 'John' })
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Insert many

  .insert([
    { name: 'Starsky' },
    { name: 'Hutch' }
  ])
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See: Insert

Modifying

{: .-three-column}

[Schema] Other methods

knex.schema
  .renameTable('persons', 'people')
  .dropTable('persons')
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  .hasTable('users').then(exists => ···)
  .hasColumn('users', 'id').then(exists => ···)
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See: Schema builder

[Schema] Alter table

knex.schema.table('accounts', table => {
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Create

  table.string('first_name')
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Alter

  table.string('first_name').alter()
  table.renameColumn('admin', 'is_admin')
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Drop

  table.dropColumn('admin')
  table.dropTimestamps('created_at')
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})
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{: .-setup}

See: Schema builder

[Schema] Create table

knex.schema.createTable('accounts', table => {
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Columns

  table.increments('id')
  table.string('account_name')
  table.integer('age')
  table.float('age')
  table.decimal('balance', 8, 2)
  table.boolean('is_admin')
  table.date('birthday')
  table.time('created_at')
  table.timestamp('created_at').defaultTo(knex.fn.now())
  table.json('profile')
  table.jsonb('profile')
  table.uuid('id').primary()
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Constraints

  table.unique('email')
  table.unique(['email', 'company_id'])
  table.dropUnique(···)
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Indices

  table.foreign('company_id')
    .references('companies.id')
  table.dropForeign(···)
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Variations

  table.integer('user_id')
    .unsigned()
    .references('users.id')
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})
.then(() => ···)
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{: .-setup}

See: Schema builder

[Select] Etc

knex('users')
  .pluck('id')
  .then(ids => { ··· })
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knex('users')
  .first()
  .then(user => { ··· })
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Booleans

  .count('active')
  .count('active as is_active')
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Numbers

  .min('age')
  .max('age')
  .sum('age')
  .sumDistinct('age')
  .avg('age')
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See: Query builder

[Select] Others

knex('users')
  .distinct()
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Group

  .groupBy('count')
  .groupByRaw('year WITH ROLLUP')
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Order

  .orderBy('name', 'desc')
  .orderByRaw('name DESC')
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Offset/limit

  .offset(10)
  .limit(20)
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Having

  .having('count', '>', 100)
  .havingIn('count', [1, 100])
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Union

  .union(function() {
    this.select(···)
  })
  .unionAll(···)
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See: Query builder

Reference

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