SQL triggers are special types of stored procedures that are automatically executed in response to specific events or actions that occur in a database. Triggers can be defined to execute in response to events such as inserts, updates, or deletes on tables, and can be used to enforce data integrity constraints, perform complex data validation,…(Continue Reading)
Category: SQL
SQL Tutorial – Learn sql language
SQL Indexes
SQL indexes are data structures that allow for efficient retrieval of data from a database. They are used to speed up queries and improve database performance by reducing the amount of data that needs to be scanned to find the desired information. Indexes are created on one or more columns in a table, and they…(Continue Reading)
SQL Views
SQL views are virtual tables that are created using a SELECT statement in SQL. A view is a database object that acts as a filter to the data stored in one or more tables. It is a logical representation of data in a database that can be used to simplify the complexity of data and…(Continue Reading)
DROP
The SQL DROP statement is used to delete or remove database objects such as tables, views, indexes, stored procedures, functions, and triggers from a database. The syntax for the DROP statement is relatively simple and straightforward, but it is important to exercise caution when using this statement because it permanently deletes the specified database objects.…(Continue Reading)
ALTER
The SQL ALTER statement is used to modify the structure of existing database objects such as tables, views, procedures, functions, and triggers. The ALTER statement allows you to change the properties of an existing object without having to drop and recreate it. Syntax The syntax for the ALTER statement varies depending on the type of…(Continue Reading)
CREATE
The SQL CREATE statement is used to create a new table, view, index, or other object in a database. It is one of the most fundamental and widely used SQL commands, and it allows database administrators and developers to define the structure and properties of database objects. Syntax The syntax for the CREATE statement is…(Continue Reading)
ROLLBACK
In SQL, a ROLLBACK statement is used to undo a transaction that is currently in progress. When a transaction is started, SQL begins keeping track of all the changes made to the database during that transaction. If at any point during the transaction an error occurs or if the user decides to cancel the transaction,…(Continue Reading)
COMMIT
In SQL language, the COMMIT statement is used to permanently save changes made to the database since the last COMMIT or ROLLBACK statement was executed. Syntax The syntax for the SQL COMMIT statement is as follows: COMMIT; The COMMIT statement is used in conjunction with the transaction management commands, which allow you to group multiple…(Continue Reading)
SQL Statements
SQL language is used to manage and manipulate data stored in relational databases. SQL statements are commands that are used to interact with a database, and they can be used to perform a wide range of tasks, from querying and updating data to creating and deleting tables. There are different types of SQL statements that…(Continue Reading)
SQL Operators
SQL operators are special symbols or keywords that are used to perform various operations on data stored in a database. These operators are used to retrieve, modify, and manipulate data in a database. In this response, I will describe some of the most common SQL operators. Arithmetic operators: Arithmetic operators are used to perform mathematical…(Continue Reading)