Querying
A query language allows users to manipulate and retrieve data from a database. While it supports easy access to large data sets, a query language is not a programming language for complex applications. Understanding algebra and calculus is key to understanding SQL.
SQL** is a declarative programming paradigm. The acronym is a shortened version of SEQUEL, which stands for Structured English Query Language. SQL is a standard language for accessing and manipulating databases.
Although SQL is an ANSI/ISO standard, there are different versions of the SQL language. Each database product may have slight variations to data types and query syntax, but for the most part the logic behind expressions is largely the same. To be compliant with the ANSI standard, they all support at least the major commands (such as SELECT, UPDATE, DELETE, INSERT, WHERE) in a similar manner.
The format of a query is:
SELECT <column>
FROM <table>;
The uppercase is not required, it is for readability.
Examples of selecting a column
Learning SQL Queries
Here are some places to learn more about SQL queries.