Category Archives: sql

SQL – Composite Key Table of content The SQL Composite Key An SQL Composite Key is a key that can be defined on two or more columns in a table to uniquely identify any record. It can also be described as a Primary Key created on multiple columns. Composite Keys are necessary in scenarios where […]

SQL – Alternate Key Table of content The SQL Alternate Key SQL Alternate Keys in a database table are candidate keys that are not currently selected as a primary key. They can be used to uniquely identify a tuple(or a record) in a table. There is no specific query or syntax to set the alternate […]

SQL – Indexes Table of content The SQL Indexes SQL Indexes are special lookup tables that are used to speed up the process of data retrieval. They hold pointers that refer to the data stored in a database, which makes it easier to locate the required data records in a database table. SQL Indexes work […]