The data type is a guideline for SQL to understand what type of data is expected inside of each column, and it also identifies how SQL will interact with the stored data. Note: Data types might have different names in different database.

The SQL ALL Operator. The ALL operator: returns a boolean value as a result; returns TRUE if ALL of the subquery values meet the condition; is used with SELECT, WHERE and HAVING statements; ALL means that the condition will be true only if the operation is true for all values in the range. ALL Syntax With SELECT

The data type is a guideline for SQL to understand what type of data is expected inside of each column, and it also identifies how SQL will interact with the stored data. In MySQL there are three main data types: string, numeric, and date and time.

SQL is a standard language for storing, manipulating and retrieving data in databases. Our SQL tutorial will teach you how to use SQL in: MySQL, SQL Server, MS Access, Oracle, Sybase, Informix, Postgres, and other database systems.

What is SQL? SQL stands for Structured Query Language; SQL lets you access and manipulate databases; SQL became a standard of the American National Standards Institute (ANSI) in 1986, and of the International Organization for Standardization (ISO) in 1987

SQL Date Data Types. MySQL comes with the following data types for storing a date or a date/time value in the database: DATE - format YYYY-MM-DD; DATETIME - format: YYYY-MM-DD HH:MI:SS; TIMESTAMP - format: YYYY-MM-DD HH:MI:SS; YEAR - format YYYY or YY; SQL Server comes with the following data types for storing a date or a date/time value in the ...

Some of The Most Important SQL Commands. SELECT - extracts data from a database; UPDATE - updates data in a database; DELETE - deletes data from a database; INSERT INTO - inserts new data into a database; CREATE DATABASE - creates a new database; ALTER DATABASE - modifies a database; CREATE TABLE - creates a new table; ALTER TABLE - …

Replaces all occurrences of a substring within a string, with a new substring: REVERSE: Reverses a string and returns the result: RIGHT: Extracts a number of characters from a string (starting from right) RPAD: Right-pads a string with another string, to a certain length: RTRIM: Removes trailing spaces from a string: SPACE

SQL ALTER TABLE Statement. The ALTER TABLE statement is used to add, delete, or modify columns in an existing table. The ALTER TABLE statement is also used to add and drop various constraints on an existing table.

Deletes the data inside a table, but not the table itself: UNION: Combines the result set of two or more SELECT statements (only distinct values) UNION ALL: Combines the result set of two or more SELECT statements (allows duplicate values) UNIQUE: A constraint that ensures that all values in a column are unique: UPDATE: Updates existing rows in ...