What is The SQL language
SQL is an acronym for Structured Query Language. SQL is used to communicate with relational databases. SQL statements are used to perform tasks such as update data in a database, or retrieve data from a database. For example, the SQL SELECT statement is used to query the database and return a set of data rows. Some common relational database management systems that use SQL include Microsoft SQL Server, MySQL, PostgreSQL, MariaDB, and Oracle.
There is a SQL language standard defined by the American National Standards Institute (ANSI). Each vendor adds their own variations and extensions.
In this module, you will learn how to:
- Understand what SQL is and how it is used
- Identify database objects in schemas
- Identify SQL statement types
- Use the SELECT statement to query tables in a database
- Work with data types
- Handle NULLs