You can rename a schema using the ALTER SCHEMA statement. Here’s the basic syntax for renaming a schema: ALTER SCHEMA old_schema_name RENAME TO new_schema_name; Replace old_schema_name with the current name of the schema you want to rename, and new_schema_name with the new name you want to assign to the schema. Here’s an example: ALTER SCHEMA…
You can create a new schema using the CREATE SCHEMA statement. A schema is a namespace that can contain tables, views, functions, and other database objects. Here’s the basic syntax for creating a schema: CREATE SCHEMA schema_name; Replace schema_name with the name you want to give to your new schema. Here’s a complete example: CREATE…
The current_schema is a function that returns the name of the currently active schema for the current session. A schema in PostgreSQL is a namespace that contains tables, views, functions, and other database objects. By default, when you create a new database session, it is associated with a specific schema, often the public schema. You…
The ROLLBACK PREPARED command is used to roll back a prepared transaction in PostgreSQL database. Prepared transactions are a feature that allows you to prepare a transaction for execution and then later commit or roll back that transaction using a unique identifier known as the transaction’s name or identifier. Here’s the syntax for the ROLLBACK…
A savepoint is a feature that allows you to create a named point within a transaction to which you can later roll back, while leaving the rest of the transaction intact. Savepoints are useful when you want to handle errors or exceptions within a transaction and selectively roll back to a specific point in the…
The ROLLBACK statement is used to undo all changes made within the current transaction and discard those changes. It effectively cancels the transaction and restores the database to its state before the transaction began. Here’s how you typically use the ROLLBACK statement in PostgreSQL: Start a transaction using the BEGIN statement: BEGIN; This begins a…
The COMMIT statement is used to permanently save any changes made within a transaction to the PostgreSQL database. PostgreSQL, like many other relational database management systems, uses transactions to group a series of database operations into a single unit of work. The COMMIT statement is issued to confirm that the changes made within a transaction…
The strpos function in PostgreSQL database is used to find the position of a substring within a given string. It returns the position (counting from 1) of the first occurrence of the substring within the string. If the substring is not found, it returns 0. Here’s the syntax for the strpos function: strpos(source_string, search_string) Here’s…
The initcap function in PostgreSQL database is used to capitalize the first letter of each word in a string, while converting all other letters to lowercase. It’s often used to format text in a more readable or proper case. Here’s the syntax for the initcap function: initcap(input_string) The initcap function takes the input_string and returns…
The rpad function in PostgreSQL database is used to right-pad a string with a specified character or a set of characters until the resulting string reaches a specified length. This function is often used to format strings to a fixed width. Here’s the syntax for the rpad function: rpad(input_string, length, pad_string) The rpad function takes…