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How to Create an Auto-increment Column Using SEQUENCES in PostgreSQL

In PostgreSQL, a sequence can be linked with a table’s column to create an auto-incremented column. For this, use the “CREATE SEQUENCE” command along with the “OWNED BY” clause.

How to Use ALTER SEQUENCE Command in PostgreSQL

In PostgreSQL, the ALTER SEQUENCE command allows us to alter the defined parameters of an already existing sequence.

How to Fix Sequence “START Value can’t be Greater Than MAXVALUE” Error in PostgreSQL

“START Value can’t be Greater Than MAXVALUE” error occurs because of two reasons: if the start value is greater than the maximum value or if the user specified an out-of-the-range value.

How Do I List Sequences in PostgreSQL

In PostgreSQL, the “\ds” command, “information_schema”, and “pg_class” catalog are used to get the list of available sequences.

How to Update a View in PostgreSQL?

In PostgreSQL, an already created view can be altered by utilizing the UPDATE query followed by the view name and then specifying the column to be updated in the SET clause.

How to Sort a Table by Month Name in PostgreSQL

To sort a table by month name use the ORDER BY clause alongside the EXTRACT() and TO_DATE() functions. 'Month' must be specified as an argument to the EXTRACT() and TO_DATE() functions.

How to Use UPDATE RETURNING Clause in PostgreSQL

In PostgreSQL, the UPDATE RETURNING clause not only updates the selected rows but also retrieves the modified rows.

How to Drop a Sequence in PostgreSQL

To remove a Postgres sequence, execute the “DROP SEQUENCE” command followed by the sequence name to be dropped.

How to List Constraints of a Table in PostgreSQL?

In PostgreSQL, the “\d” command and “pg_catalog” schema with the “pg_constraint” and “pg_class” views are used to get the list of table constraints.

How to Select One Row From Each Group in PostgreSQL?

In PostgreSQL, the “SELECT DISTINCT ON” statement is used to select one row per group. The stated command selects and retrieves a random row from each group.