Inserting, updating, and deleting records in database tables using PHP Mocktest

The pdo_query() function in PHP PDO extension is used to execute an SQL query. It sends an SQL query to the database and returns a PDOStatement object representing the result set (if applicable).

The mysqli_num_rows() function in PHP is used to get the number of rows in a result set returned by a SELECT query. It returns the number of rows or false if the query does not return a result set.

The CREATE statement in SQL is used to create a new database table with the specified name and column definitions. It defines the structure of the table, including column names, data types, and constraints.

The PDO::lastInsertId() method in PHP PDO extension is used to retrieve the ID generated by the last INSERT statement. It is commonly used to obtain the primary key value of the last inserted row in an auto-increment column.

The TRUNCATE operation in SQL is used to remove all records (rows) from a database table. Unlike the DELETE operation, which removes specific rows, TRUNCATE removes all rows from the table.

The mysqli_close() function in PHP is used to close a previously opened database connection. It releases the resources associated with the connection and frees up memory, helping improve the performance of the PHP application.

The mysqli_query() function in PHP MySQLi extension is used to execute an SQL query. It sends an SQL query to the MySQL database and returns a result object for SELECT queries or a boolean value for other types of queries.

The PDO::beginTransaction() method in PHP PDO extension is used to initiate a transaction. It marks the beginning of a transaction block, allowing multiple database operations to be grouped together and treated as a single unit of work.

The ALTER operation in SQL is used to modify the structure of an existing database table. It allows you to add, modify, or drop columns, change data types, and apply constraints to the table.

The PDO::commit() method in PHP PDO extension is used to commit a transaction. It makes all changes made during the transaction permanent and finalizes the transaction, allowing other transactions to see the changes.