SQL

SQL SELECT DISTINCT

SQL DISTINCT clause is used to remove duplicate records. SELECT DISTINCT returns distinct(different) values. DISTINCT can be used with aggregate functions: COUNT, AVG, MAX, MIN. Syntax: SQL SELECT DISTINCT based on one column You can SELECT DISTINCT values from one column in a table. Below is the syntax. SQL SELECT DISTINCT based on multiple columns …

SQL SELECT Statement

The SELECT statement in SQL is used to retrieve data from a database. Mostly used to retrieve all data in a table and data from desired table columns (fields). SELECT Syntax In the above syntax, you are selecting data from exact columns or fields indicated as column1, column2, column3 and so on. To select all …

What is SQL?

SQL stands for Structured Query Language. SQL is used to store, query, modify, manipulate and retrieve data stored in a relational database. Usually pronounced as “ess-que-ell”. According to ANSI (American National Standards Institute), it is the language for relational database management systems. All relational database systems (RDBMS) accept the use of SQL (MS Access, MySQL, …

Top 5 Ways to Improve SQL Queries

What is Performance tuning Performance tuning in SQL is the practice of ensuring SQL queries run as fast as possible. SQL Performance tuning can be difficult, especially when working with large amount of data. SQL performance tuning is handled by Database Administrators (DBA’s) in large corporations. However, to improve the speed of data retrieval with …

SQL For Data Science

The understanding of data trends, patterns, attributes and its relationship to human behavior and business is a result of data-driven cycle in analytics. Data Science revolves around data. We associate quarterly and annual growth of businesses based on data received which are facts to help make business decisions. Most improved business methodologies are data-driven. So, …

SQL Query to Reduce Redundancy of Data

What is Data Data is a collection of words, images, sound, letters and observations for analysis, reference and research purpose. What is Redundancy in Data Data redundancy is the duplication of data in a table or database. When data is duplicated we consume more memory space in storage devices . Back-up storage devices can be …