Category: SQL

A non-clustered index in SQL is a data structure that improves the performance of queries by providing a quick access path to the data. Unlike a clustered index, which determines the physical order of the data in a table, a non-clustered index creates a separate structure that contains a sorted copy of the indexed column(s)…(Continue Reading)

A clustered index in SQL is a type of index that determines the physical order of data in a table. It defines the order in which the rows of a table are stored on disk or other storage media. Unlike a non-clustered index, which creates a separate structure to store index data, a clustered index…(Continue Reading)

The CREATE TRIGGER statement in SQL Server is used to create a database object that automatically executes a set of SQL statements when a specific event occurs in the database. This event can be an INSERT, UPDATE, or DELETE operation on a table or view. Syntax The syntax of the CREATE TRIGGER statement in SQL…(Continue Reading)

In SQL, an index is a database object used to speed up the retrieval of data from tables. It works by creating a data structure that allows the database management system (DBMS) to quickly locate the rows of a table that match a particular search criteria. By creating an index on one or more columns…(Continue Reading)

SQL CREATE VIEW statement is used to create a virtual table that is based on the result set of a SELECT statement. A view does not store any data of its own; instead, it references data from one or more tables in the database. Views are used to simplify complex queries and to provide a…(Continue Reading)

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)

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 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)

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)

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)