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  1. 30 Ιουν 2014 · I am trying to drop table if it is exists in the present working database of PostgreSQL. For which I am trying the following query. Example: var1 := 'IF EXISTS (select * from INFORMATION_SCHEMA.TABLES WHERE name = ''Table_'|| Suffix ||''') then DROP TABLE Table_'||Suffix||''; execute var1; But getting error near IF.

  2. 5 Ιαν 2022 · In PostgreSQL, we can use the IF EXISTS clause of the DROP TABLE statement to check whether the table exists or not before dropping it. Example. Here’s an example to demonstrate: DROP TABLE IF EXISTS t1; That statement drops a table called t1 if it exists.

  3. 23 Δεκ 2023 · In SQL, we can use the DROP TABLE IF EXISTS statement to drop a table only if it exists. While it may seem obvious that we can only drop a table if it exists (i.e. we can’t drop a table that doesn’t exist), there’s a good reason for using this statement.

  4. 4 Ιαν 2024 · To avoid this, PostgreSQL provides a way to conditionally drop a table using the IF EXISTS clause: DROP TABLE IF EXISTS table_name; Using the EXISTS Condition. You can also check for the existence of a table using a subquery with the EXISTS keyword.

  5. 26 Σεπ 2024 · DROP TABLE removes tables from the database. Only the table owner, the schema owner, and superuser can drop a table. To empty a table of rows without destroying the table, use DELETE or TRUNCATE. DROP TABLE always removes any indexes, rules, triggers, and constraints that exist for the target table.

  6. 26 Σεπ 2024 · DROP DATABASE drops a database. It removes the catalog entries for the database and deletes the directory containing the data. It can only be executed by the database owner. It cannot be executed while you are connected to the target database.

  7. When I DROP a table with the IF EXISTS clause (in PostgreSQL 11.x), it issues a warning as follows: => DROP TABLE IF EXISTS tt; NOTICE: table "tt" does not exist, skipping. Sometimes, I do expect that certain tables to not exist, and don't want to see many warnings like these in the output of a batch processing function/script.