Schema Builder

The knex.schema is a getter function, which returns a stateful object containing the query. Therefore be sure to obtain a new instance of the knex.schema for every query. These methods return promises.

Essentials

withSchema

knex.schema.withSchema([schemaName])

Specifies the schema to be used when using the schema-building commands.

knex.schema.withSchema('public').createTable('users', function (table) {
  table.increments();
})

createTable

knex.schema.createTable(tableName, callback)

Creates a new table on the database, with a callback function to modify the table's structure, using the schema-building commands.

knex.schema.createTable('users', function (table) {
  table.increments();
  table.string('name');
  table.timestamps();
})

createTableLike

knex.schema.createTableLike(tableName, tableNameToCopy, [callback])

Creates a new table on the database based on another table. Copy only the structure : columns, keys and indexes (expected on SQL Server which only copy columns) and not the data. Callback function can be specified to add columns in the duplicated table.

knex.schema.createTableLike('new_users', 'users')

// "new_users" table contains columns 
// of users and two new columns 'age' and 'last_name'.
knex.schema.createTableLike('new_users', 'users', (table) => {
  table.integer('age');
  table.string('last_name');
})

dropTable

knex.schema.dropTable(tableName)

Drops a table, specified by tableName.

knex.schema.dropTable('users')

dropTableIfExists

knex.schema.dropTableIfExists(tableName)

Drops a table conditionally if the table exists, specified by tableName.

knex.schema.dropTableIfExists('users')

renameTable

knex.schema.renameTable(from, to)

Renames a table from a current tableName to another.

knex.schema.renameTable('users', 'old_users')

hasTable

knex.schema.hasTable(tableName)

Checks for a table's existence by tableName, resolving with a boolean to signal if the table exists.

knex.schema.hasTable('users').then(function(exists) {
  if (!exists) {
    return knex.schema.createTable('users', function(t) {
      t.increments('id').primary();
      t.string('first_name', 100);
      t.string('last_name', 100);
      t.text('bio');
    });
  }
});

hasColumn

knex.schema.hasColumn(tableName, columnName)

Checks if a column exists in the current table, resolves the promise with a boolean, true if the column exists, false otherwise.

table

knex.schema.table(tableName, callback)

Chooses a database table, and then modifies the table, using the Schema Building functions inside of the callback.

knex.schema.table('users', function (table) {
  table.dropColumn('name');
  table.string('first_name');
  table.string('last_name');
})

alterTable

knex.schema.alterTable(tableName, callback)

Chooses a database table, and then modifies the table, using the Schema Building functions inside of the callback.

knex.schema.alterTable('users', function (table) {
  table.dropColumn('name');
  table.string('first_name');
  table.string('last_name');
})

createView

knex.schema.createView(tableName, callback)

Creates a new view on the database, with a callback function to modify the view's structure, using the schema-building commands.

knex.schema.createView('users_view', function (view) {
  view.columns(['first_name']);
  view.as(knex('users').select('first_name').where('age','>', '18'));
})

createViewOrReplace

knex.schema.createViewOrReplace(tableName, callback)

Creates a new view or replace it on the database, with a callback function to modify the view's structure, using the schema-building commands. You need to specify at least the same columns in same order (you can add extra columns). In SQLite, this function generate drop/create view queries (view columns can be different).

knex.schema.createViewOrReplace('users_view', function (view) {
  view.columns(['first_name']);
  view.as(knex('users').select('first_name').where('age','>', '18'));
})

createMaterializedView

knex.schema.createMaterializedView(viewName, callback)

Creates a new materialized view on the database, with a callback function to modify the view's structure, using the schema-building commands. Only on PostgreSQL, CockroachDb, Redshift and Oracle.

knex.schema.createMaterializedView('users_view', function (view) {
  view.columns(['first_name']);
  view.as(knex('users').select('first_name').where('age','>', '18'));
})

refreshMaterializedView

knex.schema.refreshMaterializedView(viewName)

Refresh materialized view on the database. Only on PostgreSQL, CockroachDb, Redshift and Oracle.

knex.schema.refreshMaterializedView('users_view')

dropView

knex.schema.dropView(viewName)

Drop view on the database.

knex.schema.dropView('users_view')

dropViewIfExists

knex.schema.dropViewIfExists(viewName)

Drop view on the database if exists.

knex.schema.dropViewIfExists('users_view')

dropMaterializedView

knex.schema.dropMaterializedView(viewName)

Drop materialized view on the database. Only on PostgreSQL, CockroachDb, Redshift and Oracle.

knex.schema.dropMaterializedView('users_view')

dropMaterializedViewIfExists

knex.schema.dropMaterializedViewIfExists(viewName)

Drop materialized view on the database if exists. Only on PostgreSQL, CockroachDb, Redshift and Oracle.

knex.schema.dropMaterializedViewIfExists('users_view')

renameView

knex.schema.renameView(viewName)

Rename a existing view in the database. Not supported by Oracle and SQLite.

knex.schema.renameView('users_view')

alterView

knex.schema.alterView(viewName)

Alter view to rename columns or change default values. Only available on PostgreSQL, MSSQL and Redshift.

knex.schema.alterView('view_test', function (view) {
  view.column('first_name').rename('name_user');
  view.column('bio').defaultTo('empty');
})

generateDdlCommands

knex.schema.generateDdlCommands()

Generates complete SQL commands for applying described schema changes, without executing anything. Useful when knex is being used purely as a query builder. Generally produces same result as .toSQL(), with a notable exception with SQLite, which relies on asynchronous calls to the database for building part of its schema modification statements

const ddlCommands = knex.schema.alterTable(
  'users',
  (table) => {
    table
      .foreign('companyId')
      .references('company.companyId')
      .withKeyName('fk_fkey_company');
  }
).generateDdlCommands();

raw

knex.schema.raw(statement)

Run an arbitrary sql query in the schema builder chain.

knex.schema.raw("SET sql_mode='TRADITIONAL'")
  .table('users', function (table) {
    table.dropColumn('name');
    table.string('first_name');
    table.string('last_name');
  })

queryContext

knex.schema.queryContext(context)

Allows configuring a context to be passed to the wrapIdentifier hook. The context can be any kind of value and will be passed to wrapIdentifier without modification.

knex.schema.queryContext({ foo: 'bar' })
  .table('users', function (table) {
    table.string('first_name');
    table.string('last_name');
  })

The context configured will be passed to wrapIdentifier for each identifier that needs to be formatted, including the table and column names. However, a different context can be set for the column names via table.queryContext.

Calling queryContext with no arguments will return any context configured for the schema builder instance.

dropSchema

knex.schema.dropSchema(schemaName, [cascade])

Drop a schema, specified by the schema's name, with optional cascade option (default to false). Only supported by PostgreSQL.

//drop schema 'public'
knex.schema.dropSchema('public')
//drop schema 'public' cascade
knex.schema.dropSchema('public', true)

dropSchemaIfExists

knex.schema.dropSchemaIfExists(schemaName, [cascade])

Drop a schema conditionally if the schema exists, specified by the schema's name, with optional cascade option (default to false). Only supported by PostgreSQL.

//drop schema if exists 'public'
knex.schema.dropSchemaIfExists('public')
//drop schema if exists 'public' cascade
knex.schema.dropSchemaIfExists('public', true)

Schema Building

dropColumn

table.dropColumn(name)

Drops a column, specified by the column's name

dropColumns

*table.dropColumns(columns)

Drops multiple columns, taking a variable number of column names.

renameColumn

table.renameColumn(from, to)

Renames a column from one name to another.

increments

table.increments(name, options={[primaryKey: boolean = true])

Adds an auto incrementing column. In PostgreSQL this is a serial; in Amazon Redshift an integer identity(1,1). This will be used as the primary key for the table if the column isn't in another primary key. Also available is a bigIncrements if you wish to add a bigint incrementing number (in PostgreSQL bigserial). Note that a primary key is created by default if the column isn't in primary key (with primary function), but you can override this behaviour by passing the primaryKey option. If you use this function with primary function, the column is added to the composite primary key. With SQLite, autoincrement column need to be a primary key, so if primary function is used, primary keys are transformed in unique index. MySQL don't support autoincrement column without primary key, so multiple queries are generated to create int column, add increments column to composite primary key then modify the column to autoincrement column.

// create table 'users' 
// with a primary key using 'increments()'
knex.schema.createTable('users', function (table) {
  table.increments('userId');
  table.string('name');
});

// create table 'users' 
// with a composite primary key ('userId', 'name'). 
// increments doesn't generate primary key.
knex.schema.createTable('users', function (table) {
  table.primary(['userId', 'name']);
  table.increments('userId');
  table.string('name');
});

// reference the 'users' primary key in new table 'posts'
knex.schema.createTable('posts', function (table) {
  table.integer('author').unsigned().notNullable();
  table.string('title', 30);
  table.string('content');

  table.foreign('author').references('userId').inTable('users');
});

A primaryKey option may be passed, to disable to automatic primary key creation:

// create table 'users' 
// with a primary key using 'increments()'
// but also increments field 'other_id' 
// that does not need primary key
knex.schema.createTable('users', function (table) {
  table.increments('id');
  table.increments('other_id', { primaryKey: false });
});

integer

table.integer(name, length)

Adds an integer column. On PostgreSQL you cannot adjust the length, you need to use other option such as bigInteger, etc

bigInteger

table.bigInteger(name)

In MySQL or PostgreSQL, adds a bigint column, otherwise adds a normal integer. Note that bigint data is returned as a string in queries because JavaScript may be unable to parse them without loss of precision.

tinyint

table.tinyint(name, length)

Adds a tinyint column

smallint

table.smallint(name)

Adds a smallint column

mediumint

table.mediumint(name)

Adds a mediumint column

bigint

table.bigint(name)

Adds a bigint column

text

table.text(name, [textType])

Adds a text column, with optional textType for MySql text datatype preference. textType may be mediumtext or longtext, otherwise defaults to text.

string

table.string(name, [length])

Adds a string column, with optional length defaulting to 255.

float

table.float(column, [precision], [scale])

Adds a float column, with optional precision (defaults to 8) and scale (defaults to 2).

double

table.double(column, [precision], [scale])

Adds a double column, with optional precision (defaults to 8) and scale (defaults to 2). In SQLite/MSSQL this is a float with no precision/scale; In PostgreSQL this is a double precision; In Oracle this is a number with matching precision/scale.

decimal

table.decimal(column, [precision], [scale])

Adds a decimal column, with optional precision (defaults to 8) and scale (defaults to 2). Specifying NULL as precision creates a decimal column that can store numbers of any precision and scale. (Only supported for Oracle, SQLite, Postgres)

boolean

table.boolean(name)

Adds a boolean column.

date

table.date(name)

Adds a date column.

datetime

table.datetime(name, options={[useTz: boolean], [precision: number]})

Adds a datetime column. By default PostgreSQL creates column with timezone (timestamptz type). This behaviour can be overriden by passing the useTz option (which is by default true for PostgreSQL). MySQL and MSSQL do not have useTz option.

A precision option may be passed:

table.datetime('some_time', { precision: 6 }).defaultTo(knex.fn.now(6))

time

table.time(name, [precision])

Adds a time column, with optional precision for MySQL. Not supported on Amazon Redshift.

In MySQL a precision option may be passed:

table.time('some_time', { precision: 6 })

timestamp

table.timestamp(name, options={[useTz: boolean], [precision: number]})

Adds a timestamp column. By default PostgreSQL creates column with timezone (timestamptz type) and MSSQL does not (datetime2). This behaviour can be overriden by passing the useTz option (which is by default false for MSSQL and true for PostgreSQL). MySQL does not have useTz option.

table.timestamp('created_at').defaultTo(knex.fn.now());

In PostgreSQL and MySQL a precision option may be passed:

table.timestamp('created_at', { precision: 6 }).defaultTo(knex.fn.now(6));

In PostgreSQL and MSSQL a timezone option may be passed:

table.timestamp('created_at', { useTz: true });

timestamps

table.timestamps([useTimestamps], [defaultToNow], [useCamelCase])

Adds created_at and updated_at columns on the database, setting each to datetime types. When true is passed as the first argument a timestamp type is used instead. Both columns default to being not null and using the current timestamp when true is passed as the second argument. Note that on MySQL the .timestamps() only have seconds precision, to get better precision use the .datetime or .timestamp methods directly with precision. If useCamelCase is true, the name of columns are createdAt and updatedAt.

dropTimestamps

table.dropTimestamps([useCamelCase])

Drops the columns created_at and updated_at from the table, which can be created via timestamps. If useCamelCase is true, the name of columns are createdAt and updatedAt.

binary

table.binary(name, [length])

Adds a binary column, with optional length argument for MySQL.

enum / enu

table.enu(col, values, [options])

Adds a enum column, (aliased to enu, as enum is a reserved word in JavaScript). Implemented as unchecked varchar(255) on Amazon Redshift. Note that the second argument is an array of values. Example:

table.enu('column', ['value1', 'value2'])

For Postgres, an additional options argument can be provided to specify whether or not to use Postgres's native TYPE:

table.enu('column', ['value1', 'value2'], { useNative: true, enumName: 'foo_type' })

It will use the values provided to generate the appropriate TYPE. Example:

CREATE TYPE "foo_type" AS ENUM ('value1', 'value2');

To use an existing native type across columns, specify 'existingType' in the options (this assumes the type has already been created):

INFO

Since the enum values aren't utilized for a native && existing type, the type being passed in for values is immaterial.

table.enu('column', null, { useNative: true, existingType: true, enumName: 'foo_type' })

If you want to use existing enums from a schema, different from the schema of your current table, specify 'schemaName' in the options:

table.enu('column', null, { useNative: true, existingType: true, enumName: 'foo_type', schemaName: 'public' })

Knex does not provide any way to alter enumerations after creation. To change an enumeration later on you must use Knex.raw, and the appropriate command for your database.

json

table.json(name)

Adds a json column, using the built-in json type in PostgreSQL, MySQL and SQLite, defaulting to a text column in older versions or in unsupported databases.

For PostgreSQL, due to incompatibility between native array and json types, when setting an array (or a value that could be an array) as the value of a json or jsonb column, you should use JSON.stringify() to convert your value to a string prior to passing it to the query builder, e.g.

knex.table('users')
  .where({id: 1})
  .update({json_data: JSON.stringify(mightBeAnArray)});

jsonb

table.jsonb(name)

Adds a jsonb column. Works similar to table.json(), but uses native jsonb type if possible.

uuid

table.uuid(name, options=({[useBinaryUuid:boolean],[primaryKey:boolean]})

Adds a uuid column - this uses the built-in uuid type in PostgreSQL, and falling back to a char(36) in other databases by default. If useBinaryUuid is true, binary(16) is used. See uuidToBin function to convert uuid in binary before inserting and binToUuid to convert binary uuid to uuid. If primaryKey is true, then for PostgreSQL the field will be configured as uuid primary key, for CockroackDB an additional default gen_random_uuid() is set on the type.

geometry

table.geometry(name)

Adds a geometry column. Supported by SQLite, MSSQL and PostgreSQL.

knex.schema.createTable(tblName, (table) => {
  table.geometry('geometryColumn');
});

geography

table.geography(name)

Adds a geography column. Supported by SQLite, MSSQL and PostgreSQL (in PostGIS extension).

knex.schema.createTable(tblName, (table) => {
  table.geography('geographyColumn');
});

point

table.point(name)

Add a point column. Not supported by CockroachDB and MSSQL.

knex.schema.createTable(tblName, (table) => {
  table.point('pointColumn');
});

comment

table.comment(value)

Sets the comment for a table.

engine

table.engine(val)

Sets the engine for the database table, only available within a createTable call, and only applicable to MySQL.

charset

table.charset(val)

Sets the charset for the database table, only available within a createTable call, and only applicable to MySQL.

collate

table.collate(val)

Sets the collation for the database table, only available within a createTable call, and only applicable to MySQL.

inherits

table.inherits(val)

Sets the tables that this table inherits, only available within a createTable call, and only applicable to PostgreSQL.

specificType

table.specificType(name, type)

Sets a specific type for the column creation, if you'd like to add a column type that isn't supported here.

index

table.index(columns, [indexName], options=({[indexType: string], [storageEngineIndexType: 'btree'|'hash'], [predicate: QueryBuilder]}))

Adds an index to a table over the given columns. A default index name using the columns is used unless indexName is specified. In MySQL, the storage engine index type may be 'btree' or 'hash' index types, more info in Index Options section : https://dev.mysql.com/doc/refman/8.0/en/create-index.html. The indexType can be optionally specified for PostgreSQL and MySQL. Amazon Redshift does not allow creating an index. In PostgreSQL, SQLite and MSSQL a partial index can be specified by setting a 'where' predicate.

knex.table('users', function (table) {
  table.index(['name', 'last_name'], 'idx_name_last_name', {
    indexType: 'FULLTEXT',
    storageEngineIndexType: 'hash',
    predicate: knex.whereNotNull('email'),
  });
});

dropIndex

table.dropIndex(columns, [indexName])

Drops an index from a table. A default index name using the columns is used unless indexName is specified (in which case columns is ignored). Amazon Redshift does not allow creating an index.

setNullable

table.setNullable(column)

Makes table column nullable.

dropNullable

table.dropNullable(column)

Makes table column not nullable. Note that this operation will fail if there are already null values in this column.

primary

table.primary(columns, options=({[constraintName:string],[deferrable:'not deferrable'|'deferred'|'immediate']})

Create a primary key constraint on table using input columns. If you need to create a composite primary key, pass an array of columns to columns. Constraint name defaults to tablename_pkey unless constraintName is specified. On Amazon Redshift, all columns included in a primary key must be not nullable. Deferrable primary constraint are supported on Postgres and Oracle and can be set by passing deferrable option to options object.

knex.schema.alterTable('users', function(t) {
  t.unique('email')
})
knex.schema.alterTable('job', function(t) {
  t.primary('email',{constraintName:'users_primary_key',deferrable:'deferred'})
})

INFO

If you want to chain primary() while creating new column you can use primary

unique

table.unique(columns, options={[indexName: string], [deferrable:'not deferrable'|'immediate'|'deferred'], [storageEngineIndexType:'btree'|'hash'], [useConstraint:true|false]})

Adds an unique index to a table over the given columns. In MySQL, the storage engine index type may be 'btree' or 'hash' index types, more info in Index Options section : https://dev.mysql.com/doc/refman/8.0/en/create-index.html. A default index name using the columns is used unless indexName is specified. If you need to create a composite index, pass an array of column to columns. Deferrable unique constraint are supported on Postgres and Oracle and can be set by passing deferrable option to options object. In MSSQL you can set the useConstraint option to true to create a unique constraint instead of a unique index.

knex.schema.alterTable('users', function(t) {
  t.unique('email')
})
knex.schema.alterTable('job', function(t) {
  t.unique(['account_id', 'program_id'], {indexName: 'users_composite_index', deferrable:'deferred', storageEngineIndexType: 'hash'})
})
knex.schema.alterTable('job', function(t) {
  t.unique(['account_id', 'program_id'], {indexName: 'users_composite_index', useConstraint:true})
})

INFO

If you want to chain unique() while creating new column you can use unique

foreign

table.foreign(columns, [foreignKeyName])[.onDelete(statement).onUpdate(statement).withKeyName(foreignKeyName).deferrable(type)]

Adds a foreign key constraint to a table for an existing column using table.foreign(column).references(column) or multiple columns using table.foreign(columns).references(columns).inTable(table).

A default key name using the columns is used unless foreignKeyName is specified.

You can also chain onDelete() and/or onUpdate() to set the reference option (RESTRICT, CASCADE, SET NULL, NO ACTION) for the operation. You can also chain withKeyName() to override default key name that is generated from table and column names (result is identical to specifying second parameter to function foreign()).

Deferrable foreign constraint is supported on Postgres and Oracle and can be set by chaining .deferrable(type)

Note that using foreign() is the same as column.references(column) but it works for existing columns.

knex.schema.table('users', function (table) {
  table.integer('user_id').unsigned()
  table.foreign('user_id').references('Items.user_id_in_items').deferrable('deferred')
})

dropForeign

table.dropForeign(columns, [foreignKeyName])

Drops a foreign key constraint from a table. A default foreign key name using the columns is used unless foreignKeyName is specified (in which case columns is ignored).

dropUnique

table.dropUnique(columns, [indexName])

Drops a unique key constraint from a table. A default unique key name using the columns is used unless indexName is specified (in which case columns is ignored).

dropPrimary

table.dropPrimary([constraintName])

Drops the primary key constraint on a table. Defaults to tablename_pkey unless constraintName is specified.

queryContext

table.queryContext(context)

Allows configuring a context to be passed to the wrapIdentifier hook for formatting table builder identifiers. The context can be any kind of value and will be passed to wrapIdentifier without modification.

knex.schema.table('users', function (table) {
  table.queryContext({ foo: 'bar' });
  table.string('first_name');
  table.string('last_name');
})

This method also enables overwriting the context configured for a schema builder instance via schema.queryContext:

knex.schema.queryContext('schema context')
  .table('users', function (table) {
    table.queryContext('table context');
    table.string('first_name');
    table.string('last_name');
})

Note that it's also possible to overwrite the table builder context for any column in the table definition:

knex.schema.queryContext('schema context')
  .table('users', function (table) {
    table.queryContext('table context');
    table.string('first_name').queryContext('first_name context');
    table.string('last_name').queryContext('last_name context');
})

Calling queryContext with no arguments will return any context configured for the table builder instance.

Chainable Methods

The following three methods may be chained on the schema building methods, as modifiers to the column.

alter

column.alter(options={[alterNullable: boolean = true, alterType: boolean = true])

Marks the column as an alter / modify, instead of the default add.

WARNING

This only works in .alterTable() and is not supported by SQlite or Amazon Redshift. Alter is not done incrementally over older column type so if you like to add notNullable and keep the old default value, the alter statement must contain both .notNullable().defaultTo(1).alter(). If one just tries to add .notNullable().alter() the old default value will be dropped. Nullable alterations are done only if alterNullable is true. Type alterations are done only if alterType is true.

knex.schema.alterTable('user', function(t) {
  t.increments().primary(); // add
  // drops previous default value from column,
  // change type to string and add not nullable constraint
  t.string('username', 35).notNullable().alter();
  // drops both not null constraint and the default value
  t.integer('age').alter();
  // if alterNullable is false, drops only the default value
  t.integer('age').alter({alterNullable : false});
  // if alterType is false, type of column is not altered.
  t.integer('age').alter({alterType : false});
});

index

column.index([indexName], options=({[indexType: string], [storageEngineIndexType: 'btree'|'hash'], [predicate: QueryBuilder]}))

Specifies a field as an index. If an indexName is specified, it is used in place of the standard index naming convention of tableName_columnName. In MySQL, the storage engine index type may be 'btree' or 'hash' index types, more info in Index Options section : https://dev.mysql.com/doc/refman/8.0/en/create-index.html. The indexType can be optionally specified for PostgreSQL and MySQL. No-op if this is chained off of a field that cannot be indexed. In PostgreSQL, SQLite and MSSQL a partial index can be specified by setting a 'where' predicate.

primary

column.primary(options=({[constraintName:string],[deferrable:'not deferrable'|'deferred'|'immediate']}));

Sets a primary key constraint on column. Constraint name defaults to tablename_pkey unless constraintName is specified. On Amazon Redshift, all columns included in a primary key must be not nullable. Deferrable primary constraint are supported on Postgres and Oracle and can be set by passing deferrable option to options object.

knex.schema.table('users', function (table) {
  table.integer('user_id').primary('email',{constraintName:'users_primary_key',deferrable:'deferred'})
})

INFO

If you want to create primary constraint on existing column use primary

unique

column.unique(options={[indexName:string],[deferrable:'not deferrable'|'immediate'|'deferred']})

Sets the column as unique. On Amazon Redshift, this constraint is not enforced, but it is used by the query planner. Deferrable unqiue constraint are supported on Postgres and Oracle and can be set by passing deferrable option to options object.

knex.schema.table('users', function (table) {
  table.integer('user_id').unique({indexName:'user_unique_id', deferrable:'immediate'})
})

INFO

If you want to create unique constraint on existing column use unique

references

column.references(column)

Sets the "column" that the current column references as a foreign key. "column" can either be "." syntax, or just the column name followed up with a call to inTable to specify the table.

inTable

column.inTable(table)

Sets the "table" where the foreign key column is located after calling column.references.

onDelete

column.onDelete(command)

Sets the SQL command to be run "onDelete".

onUpdate

column.onUpdate(command)

Sets the SQL command to be run "onUpdate".

defaultTo

column.defaultTo(value, options={[constraintName: string = undefined]))

Sets the default value for the column on an insert.

In MSSQL a constraintName option may be passed to ensure a specific constraint name:

column.defaultTo('value', { constraintName: 'df_table_value' });

unsigned

column.unsigned()

Specifies an integer as unsigned. No-op if this is chained off of a non-integer field.

notNullable

column.notNullable()

Adds a not null on the current column being created.

nullable

column.nullable()

Default on column creation, this explicitly sets a field to be nullable.

first

column.first()

Sets the column to be inserted on the first position, only used in MySQL alter tables.

after

column.after(field)

Sets the column to be inserted after another, only used in MySQL alter tables.

comment

column.comment(value)

Sets the comment for a column.

knex.schema.createTable('accounts', function(t) {
  t.increments().primary();
  t.string('email').unique().comment('This is the email field');
});

collate

column.collate(collation)

Sets the collation for a column (only works in MySQL). Here is a list of all available collations: https://dev.mysql.com/doc/refman/5.5/en/charset-charsets.html

knex.schema.createTable('users', function(t) {
  t.increments();
  t.string('email').unique().collate('utf8_unicode_ci');
});

View

columns

view.columns([columnNames])

Specify the columns of the view.

knex.schema.createView('users_view', function (view) {
  view.columns(['first_name', 'last_name']);
  view.as(knex('users').select('first_name').where('age','>', '18'));
});

as

view.as(selectQuery)

Specify the select query of the view.

checkOption

view.checkOption()

Add check option on the view definition. On OracleDb, MySQL, PostgreSQL and Redshift.

localCheckOption

view.localCheckOption()

Add local check option on the view definition. On MySQL, PostgreSQL and Redshift.

cascadedCheckOption

view.cascadedCheckOption()

Add cascaded check option on the view definition. On MySQL, PostgreSQL and Redshift.

Checks

check

table.check(checkPredicate, [bindings], [constraintName]))

Specify a check on table or column with raw predicate.

knex.schema.createTable('product', function (table) {
  table.integer('price_min');
  table.integer('price');
  table.check('?? >= ??', ['price', 'price_min']);
})

checkPositive

column.checkPositive([constraintName])

Specify a check on column that test if the value of column is positive.

knex.schema.createTable('product', function (table) {
  table.integer('price').checkPositive();
})

checkNegative

column.checkNegative([constraintName])

Specify a check on column that test if the value of column is negative.

knex.schema.createTable('product', function (table) {
  table.integer('price_decrease').checkNegative();
})

checkIn

column.checkIn(values, [constraintName])

Specify a check on column that test if the value of column is contained in a set of specified values.

knex.schema.createTable('product', function (table) {
  table.string('type').checkIn(['table', 'chair', 'sofa']);
})

checkNotIn

column.checkNotIn(values, [constraintName])

Specify a check on column that test if the value of column is not contains in a set of specified values.

knex.schema.createTable('product', function (table) {
  table.string('type').checkNotIn(['boot', 'shoe']);
})

checkBetween

column.checkBetween(values, [constraintName])

Specify a check on column that test if the value of column is within a range of values.

knex.schema.createTable('product', function (table) {
  table.integer('price').checkBetween([0, 100]);
})
// You can add checks on multiple intervals
knex.schema.createTable('product', function (table) {
  table.integer('price').checkBetween([ [0, 20], [30,40] ]);
})

checkLength

column.checkLength(operator, length, [constraintName])

Specify a check on column that test if the length of a string match the predicate.

knex.schema.createTable('product', function (table) {
  // operator can be =, !=, <=, >=, <, >
  t.varchar('phone').checkLength('=', 8);
})

checkRegex

column.checkRegex(regex, [constraintName])

Specify a check on column that test if the value match the specified regular expression. In MSSQL only simple pattern matching in supported but not regex syntax.

knex.schema.createTable('product', function (table) {
  table.string('phone').checkRegex('[0-9]{8}');
  // In MSSQL, {8} syntax don't work,
  // you need to duplicate [0-9].
  table.string('phone').checkRegex('[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]');
})

dropChecks

table.dropChecks([checkConstraintNames])

Drop checks constraint given an array of constraint names.

knex.schema.createTable('product', function (table) {
  table.integer('price').checkPositive('price_check')
  table.integer('price_proportion').checkBetween([0, 100],'price_proportion_check')
  table.dropChecks(['price_check', 'price_proportion_check']);
})