The principle difference between static and dynamic SQL statements is the point in time when the SQL statements are constructed and compiled.

A static SQL statement is embedded in a host language program and must be precompiled. The type of statement, the tables, views, columns referenced, and search conditions cannot be changed at runtime. Although host variables can be used to provide search values at runtime, the general content of the statement (for example, the derived column list or the search conditions) cannot be changed at runtime.

A dynamic SQL statement is constructed at runtime. The statement, including the tables, the referenced views and columns, and the search conditions, is compiled at runtime.

Dynamic SQL usage requires the use of the following statements:

PREPARE, EXECUTE, EXECUTE IMMEDIATE and DESCRIBE.

There are also some SQL statements which are normally used as static SQL statements, but have an extended functionality for dynamic SQL:

DECLARE CURSOR, OPEN and FETCH.

There are various methods of using dynamic SQL statements, mainly depending on the type of SQL statement (SELECT or NON-SELECT statements) and the degree of flexibility required.