Sybase 12.4.2 manual Commands and Functions, Types of SQL statements

Commands and Functions

Commands and Functions

All Adaptive Server IQ commands are SQL statements. SQL stands for Structured Query Language, a language commonly used in database applications. Adaptive Server IQ SQL uses the same syntax as Adaptive Server Anywhere SQL; the only differences are for certain product capabilities that are supported only for IQ or for Anywhere. Adaptive Server IQ SQL also offers a high degree of compatibility with Transact-SQL, the SQL dialect used by Adaptive Server Enterprise.

This section introduces the types of commands and functions you can use. Other chapters of this book tell you about the commands you use to perform various administrative tasks. For complete details of supported commands and functions, see the Adaptive Server IQ Reference Manual.

Types of SQL statements

You use three basic types of SQL statements:

•DDL (Data Definition Language) statements let you define and modify your database schema and table and index definitions. Examples of DDL

statements include CREATE TABLE, CREATE INDEX, ALTER TABLE, and DROP.

•DML (Data Manipulation Language) statements let you query your data, and move data into and out of the database. Examples of DML statements include SELECT, SET, and INSERT.

•Program control statements control the flow of program execution. They

do not operate directly on your IQ tables. Examples include IF, CALL, and

ROLLBACK.

Functions

Functions return information from the database. They are allowed anywhere an expression is allowed. Adaptive Server IQ provides functions that:

•Aggregate data (for example, AVG, COUNT, MAX, MIN, SUM)

•Manipulate numeric data (for example, ABS, CEILING, SQRT,

TRUNCATE)

• Manipulate string data (for example, LENGTH, SOUNDEX, UCASE)

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