![]() ![]() It will give you the same result as you were expecting from using serial. The second line alters your table with the new default value, which will be determined by the previously created sequence. Indexes and table constraints involving the column will be automatically dropped as well. If in doing so a BIGGER DB instance can help, we are open to explore that as well. NOTE: Our primary goal is to minimise the down time. ![]() DROP COLUMN IF EXISTS This form drops a column from a table. Create a new partitioned table with exact same configuration, b. There are several subforms: ADD COLUMN This form adds a new column to the table, using the same syntax as CREATE TABLE. You can: Add columns Remove columns Add constraints Remove constraints Change default values Change column data types Rename columns Rename tables All these actions are performed using the ALTER TABLE command, whose reference page contains details beyond those given here. The START statement defines what value this sequence should start from. Description ALTER TABLE changes the definition of an existing table. In your case the table is address and the column is new_id. OWNED BY statement connects the newly created sequence with the exact column of your table. The first line of the query creates your own sequence called my_serial. In case you would like to achieve the same effect, as you are expecting from using serial data type when you are altering existing table you may do this: CREATE SEQUENCE my_serial AS integer START 1 OWNED BY address.new_id ĪLTER TABLE address ALTER COLUMN new_id SET DEFAULT nextval('my_serial') Because serial is not a true data type, but merely an abbreviation or alias for a longer query. If you'll try to ALTER an existing table using this data type you'll get an error. This happened because you may use the serial data type only when you are creating a new table or adding a new column to a table. ![]()
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