Superusers have full control over the database server and can perform any administrative task. Granting superuser privileges to a user should be done carefully, as it comes with significant power and responsibility. To grant superuser privileges to a user in PostgreSQL, follow these steps: Option 1: During PostgreSQL Installation Option 2: Using an Existing Superuser…

To rename a column in PostgreSQL, you can use the ALTER TABLE statement with the RENAME COLUMN clause. Below is the basic syntax for renaming a column in PostgreSQL: ALTER TABLE table_name RENAME COLUMN old_column_name TO new_column_name; where table_name is the name of the table containing the column you want to rename, old_column_name is the…

To list all databases in PostgreSQL, you can use the following SQL command: SELECT datname FROM pg_database; Above query will display a list of database names currently available on the server. You should have the necessary permissions to list databases on the PostgreSQL server. If you encounter permission issues, make sure you are logged in…

To change the owner of all tables within a specific schema in PostgreSQL, you can use a combination of SQL queries to generate and execute the necessary ALTER TABLE statements. Run the following SQL query to generate a list of ALTER TABLE statements for all tables in the schema you want to change the owner…

To get the name of the current database in PostgreSQL, you can use the following SQL query: SELECT current_database(); When you execute this query, it will return the name of the database that you are currently connected to. For example, if you are connected to a database named “my_database,” executing the query will return “my_database”…

To move a table from one schema to another in PostgreSQL database, you can use the ALTER TABLE statement with the SET SCHEMA clause. Here’s the basic syntax: ALTER TABLE old_schema.table_name SET SCHEMA new_schema; where old_schema is the name of the current schema where the table resides. table_name is the name of the table you…

You can retrieve the username of the currently logged-in user using the current_user function. SELECT current_user; When you execute this SQL query, it will return the username of the currently logged-in user as a text value. You can use this information in your SQL queries or as part of your application to determine the current…

To get the size of a specific table in PostgreSQL, you can use the pg_total_relation_size function. This function returns the total size of a table in bytes, including the main data file, indexes, and associated objects. Below is the syntax: SELECT pg_size_pretty(pg_total_relation_size(‘your_table_name’)); where ‘your_table_name’ with the name of the table you want to get the…

To retrieve a list of all schemas in a PostgreSQL database, you can use the following SQL query: SELECT schema_name FROM information_schema.schemata; This query queries the information_schema.schemata view, which contains information about all the schemas in the current database. When you execute this query, it will return a list of schema names present in the…

To describe a table in PostgreSQL and retrieve information about its columns and data types, you can use the \d command in the psql command-line tool or execute a SQL query. Here are two common methods to describe a table: Method 1: Using \d in psql (Command-Line Tool): Open a terminal and start the psql…