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Represents an SQL table in an abstract way for updating a table. Also see TableDefinition and connection.create_table

Available transformations are:

change_table :table do |t|
  t.primary_key
  t.column
  t.index
  t.rename_index
  t.timestamps
  t.change
  t.change_default
  t.change_null
  t.rename
  t.references
  t.belongs_to
  t.check_constraint
  t.string
  t.text
  t.integer
  t.bigint
  t.float
  t.decimal
  t.numeric
  t.datetime
  t.timestamp
  t.time
  t.date
  t.binary
  t.boolean
  t.foreign_key
  t.json
  t.virtual
  t.remove
  t.remove_foreign_key
  t.remove_references
  t.remove_belongs_to
  t.remove_index
  t.remove_check_constraint
  t.remove_timestamps
end
Methods
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Included Modules
Attributes
[R] name
Class Public methods
new(table_name, base)
# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 574
def initialize(table_name, base)
  @name = table_name
  @base = base
end
Instance Public methods
belongs_to(*args, **options)
Alias for: references
change(column_name, type, **options)

Changes the column's definition according to the new options.

t.change(:name, :string, limit: 80)
t.change(:description, :text)

See TableDefinition#column for details of the options you can use.

# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 648
def change(column_name, type, **options)
  @base.change_column(name, column_name, type, **options)
end
change_default(column_name, default_or_changes)

Sets a new default value for a column.

t.change_default(:qualification, 'new')
t.change_default(:authorized, 1)
t.change_default(:status, from: nil, to: "draft")

See connection.change_column_default

# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 659
def change_default(column_name, default_or_changes)
  @base.change_column_default(name, column_name, default_or_changes)
end
change_null(column_name, null, default = nil)

Sets or removes a NOT NULL constraint on a column.

t.change_null(:qualification, true)
t.change_null(:qualification, false, 0)

See connection.change_column_null

# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 669
def change_null(column_name, null, default = nil)
  @base.change_column_null(name, column_name, null, default)
end
check_constraint(*args)

Adds a check constraint.

t.check_constraint("price > 0", name: "price_check")

See connection.add_check_constraint

# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 773
def check_constraint(*args)
  @base.add_check_constraint(name, *args)
end
column(column_name, type, index: nil, **options)

Adds a new column to the named table.

t.column(:name, :string)

See TableDefinition#column for details of the options you can use.

# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 584
def column(column_name, type, index: nil, **options)
  @base.add_column(name, column_name, type, **options)
  if index
    index_options = index.is_a?(Hash) ? index : {}
    index(column_name, **index_options)
  end
end
column_exists?(column_name, type = nil, **options)

Checks to see if a column exists.

t.string(:name) unless t.column_exists?(:name, :string)

See connection.column_exists?

# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 597
def column_exists?(column_name, type = nil, **options)
  @base.column_exists?(name, column_name, type, **options)
end
foreign_key(*args, **options)

Adds a foreign key to the table using a supplied table name.

t.foreign_key(:authors)
t.foreign_key(:authors, column: :author_id, primary_key: "id")

See connection.add_foreign_key

# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 745
def foreign_key(*args, **options)
  @base.add_foreign_key(name, *args, **options)
end
foreign_key_exists?(*args, **options)

Checks to see if a foreign key exists.

t.foreign_key(:authors) unless t.foreign_key_exists?(:authors)

See connection.foreign_key_exists?

# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 764
def foreign_key_exists?(*args, **options)
  @base.foreign_key_exists?(name, *args, **options)
end
index(column_name, **options)

Adds a new index to the table. column_name can be a single Symbol, or an Array of Symbols.

t.index(:name)
t.index([:branch_id, :party_id], unique: true)
t.index([:branch_id, :party_id], unique: true, name: 'by_branch_party')

See connection.add_index for details of the options you can use.

# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 609
def index(column_name, **options)
  @base.add_index(name, column_name, **options)
end
index_exists?(column_name, options = {})

Checks to see if an index exists.

unless t.index_exists?(:branch_id)
  t.index(:branch_id)
end

See connection.index_exists?

# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 620
def index_exists?(column_name, options = {})
  @base.index_exists?(name, column_name, options)
end
references(*args, **options)

Adds a reference.

t.references(:user)
t.belongs_to(:supplier, foreign_key: true)

See connection.add_reference for details of the options you can use.

Also aliased as: belongs_to
# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 719
def references(*args, **options)
  args.each do |ref_name|
    @base.add_reference(name, ref_name, **options)
  end
end
remove(*column_names, **options)

Removes the column(s) from the table definition.

t.remove(:qualification)
t.remove(:qualification, :experience)

See connection.remove_columns

# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 679
def remove(*column_names, **options)
  @base.remove_columns(name, *column_names, **options)
end
remove_belongs_to(*args, **options)
Alias for: remove_references
remove_check_constraint(*args)

Removes the given check constraint from the table.

t.remove_check_constraint(name: "price_check")

See connection.remove_check_constraint

# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 782
def remove_check_constraint(*args)
  @base.remove_check_constraint(name, *args)
end
remove_foreign_key(*args, **options)

Removes the given foreign key from the table.

t.remove_foreign_key(:authors)
t.remove_foreign_key(column: :author_id)

See connection.remove_foreign_key

# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 755
def remove_foreign_key(*args, **options)
  @base.remove_foreign_key(name, *args, **options)
end
remove_index(column_name = nil, **options)

Removes the given index from the table.

t.remove_index(:branch_id)
t.remove_index(column: [:branch_id, :party_id])
t.remove_index(name: :by_branch_party)
t.remove_index(:branch_id, name: :by_branch_party)

See connection.remove_index

# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 691
def remove_index(column_name = nil, **options)
  @base.remove_index(name, column_name, **options)
end
remove_references(*args, **options)

Removes a reference. Optionally removes a type column.

t.remove_references(:user)
t.remove_belongs_to(:supplier, polymorphic: true)

See connection.remove_reference

Also aliased as: remove_belongs_to
# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 732
def remove_references(*args, **options)
  args.each do |ref_name|
    @base.remove_reference(name, ref_name, **options)
  end
end
remove_timestamps(**options)

Removes the timestamp columns (created_at and updated_at) from the table.

t.remove_timestamps

See connection.remove_timestamps

# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 700
def remove_timestamps(**options)
  @base.remove_timestamps(name, **options)
end
rename(column_name, new_column_name)

Renames a column.

t.rename(:description, :name)

See connection.rename_column

# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 709
def rename(column_name, new_column_name)
  @base.rename_column(name, column_name, new_column_name)
end
rename_index(index_name, new_index_name)

Renames the given index on the table.

t.rename_index(:user_id, :account_id)

See connection.rename_index

# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 629
def rename_index(index_name, new_index_name)
  @base.rename_index(name, index_name, new_index_name)
end
timestamps(**options)

Adds timestamps (created_at and updated_at) columns to the table.

t.timestamps(null: false)

See connection.add_timestamps

# File activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 638
def timestamps(**options)
  @base.add_timestamps(name, **options)
end