To incorporate new columns, you must recreate the view.
ALTER TABLE ADD COLUMN UPDATE
+-Īdding new columns to a table that has an associated view does not update the view's result set, even if the view uses a wildcard (*) to represent all table columns. ORDER BY projection_name, projection_column_name => SELECT projection_column_name, projection_name FROM projection_columns WHERE table_name ILIKE 'store_orders'
=> ALTER TABLE public.store_orders ADD COLUMN delivery_date date PROJECTIONS (store_orders_p) Because the statement omits the PROJECTIONS option, Vertica adds the column only to the table's superprojection: The following ALTER TABLE…ADD COLUMN statement adds column expected_ship_date to the store_orders table.
ALL PROJECTIONS adds the column to all projections of this table, excluding projections with pre-aggregated data.įor example, the store_orders table has two projections-superprojection store_orders_super, and user-created projection store_orders_p. The projection list cannot include projections with pre-aggregated data such as live aggregate projections otherwise, Vertica rolls back the ALTER TABLE statement. Vertica adds the column to all buddies of each projection. The ALTER TABLE command can add or delete columns, create or destroy indexes, change the type of existing columns, or rename columns or the table itself. PROJECTIONS ( projections-list): Adds the new column to one or more projections of this table, specified as a comma-delimted list of projection base names. The ADD…COLUMN clause can also specify to add the column to one or more non-superprojections, with one of these options: When you add a column to a table, Vertica automatically adds the column to superprojections of that table. The lock also blocks SELECT statements issued at SERIALIZABLE isolation level, until the operation completes.Īdding a column to a table does not affect K-safety of the physical schema design. The lock prevents DELETE, UPDATE, INSERT, and COPY statements from accessing the table. When you use ADD COLUMN to alter a table, Vertica takes an O lock on the table until the operation completes. Syntax: ALTER TABLE table ADD columnname newdatatype NULL NOT NULL PRIMARY KEY UNIQUE. However, if the table has records, first add the new column allowing NULL, update the data, then in the final step change the definition of the column to NOT NULL.Before you add columns to a table, verify that all its superprojections are up to date. It is possible to add, delete or change the column. At the end of the statement, we specify varchar(100) as the datatype for the values that will be stored in the column color, and the constraint NOT NULL because we don’t want to allow empty values in this column. We specify the column to be named, color, after the ADD keyword. 
The name of the table, jeans follows the ALTER TABLE. In the example above, we modified the structure of the table jeans. After the ADD, you define the column in the same way as when you create a new table (after the CREATE TABLE in parentheses). It is then followed by the definition of the column: the datatype and any additional constraints. Key points of SQL alter table add column statement Using the ALTER TABLE statement to add columns to a table automatically adds those columns to the end of the. The next is the keyword ADD, after which the name of the new column is specified. Alter table add column statement is used to modify the structure of the table and used to add the column to the table. Place the ALTER TABLE keyword followed by the name of the table you want to change. It is used to modify the table by adding a new column. SQL provides the statement ALTER TABLE that allows you to change the structure of a table.
The new column is not back-populated even if the table contains data. We would like to add the column color of the datatype varchar to the table called jeans. Adds a new column of a specified type to an existing table. You want to add a new column to an existing table.
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