SQL Language elements

The SQL language is subdivided into several language elements, including:

Clauses, which are constituent components of statements and queries.
Expressions, which can produce either scalar values, or tables consisting of columns and rows of data
Predicates, which specify conditions that can be evaluated to SQL three-valued logic(true/false/unknown) or Boolean truth values and are used to limit the effects of statements and queries, or to change program flow.
Queries, which retrieve the data based on specific criteria
Statements, which may have a persistent effect on schemata and data, or may control transactions, program flow, connections, sessions, or diagnostics.
Insignificant whitespace is generally ignored in SQL statements and queries