- Inheritance
- < Object
Represents a SQL table in an abstract way for updating a table. Also see TableDefinition and SchemaStatements#create_table
Available transformations are:
change_table :table do |t|
t.column
t.index
t.timestamps
t.change
t.change_default
t.rename
t.references
t.belongs_to
t.string
t.text
t.integer
t.float
t.decimal
t.datetime
t.timestamp
t.time
t.date
t.binary
t.boolean
t.remove
t.remove_references
t.remove_belongs_to
t.remove_index
t.remove_timestamps
end
Methods
Class
| Visibility | Signature |
|---|---|
| public | new (table_name, base) |
Instance
| Visibility | Signature |
|---|---|
| public | belongs_to (*args) |
| public | change (column_name, type, options = {}) |
| public | change_default (column_name, default) |
| public | column (column_name, type, options = {}) |
| public | index (column_name, options = {}) |
| public | references (*args) |
| public | remove (*column_names) |
| public | remove_belongs_to (*args) |
| public | remove_index (options = {}) |
| public | remove_references (*args) |
| public | remove_timestamps () |
| public | rename (column_name, new_column_name) |
| public | timestamps () |
Class Method Detail
new(table_name, base)
Instance Method Detail
belongs_to(*args)
Alias for references
change(column_name, type, options = {})
Changes the column‘s definition according to the new options. See TableDefinition#column for details of the options you can use.
Examples
t.change(:name, :string, :limit => 80) t.change(:description, :text)
change_default(column_name, default)
Sets a new default value for a column. See SchemaStatements#change_column_default
Examples
t.change_default(:qualification, 'new') t.change_default(:authorized, 1)
column(column_name, type, options = {})
Adds a new column to the named table. See TableDefinition#column for details of the options you can use.
Example
Creating a simple column
t.column(:name, :string)
index(column_name, options = {})
Adds a new index to the table. column_name can be a single Symbol, or an Array of Symbols. See SchemaStatements#add_index
Examples
Creating a simple index
t.index(:name)
Creating a unique index
t.index([:branch_id, :party_id], :unique => true)
Creating a named index
t.index([:branch_id, :party_id], :unique => true, :name => 'by_branch_party')
references(*args)
Adds a reference. Optionally adds a type column. references and belongs_to are acceptable.
Examples
t.references(:goat) t.references(:goat, :polymorphic => true) t.belongs_to(:goat)
remove(*column_names)
Removes the column(s) from the table definition.
Examples
t.remove(:qualification) t.remove(:qualification, :experience)
remove_belongs_to(*args)
Alias for remove_references
remove_index(options = {})
Removes the given index from the table.
Examples
Remove the suppliers_name_index in the suppliers table
t.remove_index :name
Remove the index named accounts_branch_id_index in the accounts table
t.remove_index :column => :branch_id
Remove the index named accounts_branch_id_party_id_index in the accounts table
t.remove_index :column => [:branch_id, :party_id]
Remove the index named by_branch_party in the accounts table
t.remove_index :name => :by_branch_party
remove_references(*args)
Removes a reference. Optionally removes a type column. remove_references and remove_belongs_to are acceptable.
Examples
t.remove_references(:goat) t.remove_references(:goat, :polymorphic => true) t.remove_belongs_to(:goat)
remove_timestamps()
Removes the timestamp columns (created_at and updated_at) from the table.
Example
t.remove_timestamps
rename(column_name, new_column_name)
timestamps()
Adds timestamps (created_at and updated_at) columns to the table. See SchemaStatements#add_timestamps
Example
t.timestamps