How to Add Column to PostgreSQL Table

PostgreSQL Add Column

To add a new column to an existing PostgreSQL Table, use the following ALTER TABLE syntax.

ALTER TABLE table_name
	ADD COLUMN new_column_name data_type;

Example Add Column to PostgreSQL Table

Consider the following table, where we have three columns.

Now we will add a new column named attendance to this table.

ALTER TABLE students
	ADD COLUMN attendance INTEGER;

A new column with the name attendance and datatype of integer has been added to the Table. But the value for this column for each row has been null.

Example Add Column with a Default Value

To add a new column with some default value other than null, use the following ALTER TABLE syntax.

ALTER TABLE table_name
	ADD COLUMN new_column_name data_type NOT NULL DEFAULT default_value;

Let us create a column named attendance with default value of 84.

The contents of the table after executing the ALTER TABLE … ADD COLUMN … would be

Conclusion

In this PostgreSQL Tutorial, we have added a new column to PostgreSQL Table. Also, we have seen how to add a column with a default value.