15.00 - Invoking SQL Statements - Teradata Database

Invoking SQL Statements

SQL provides several ways to invoke an executable SQL statement:

Interactively from a terminal

Embedded within an application program

Dynamically performed from within an embedded application

Embedded within a stored procedure or external stored procedure

Executable SQL Statements

An executable SQL statement performs an action. The action can be on data or on a transaction or some other entity at a higher level than raw data.

Some examples of executable SQL statements include:

SELECT

CREATE TABLE

COMMIT

CONNECT

PREPARE

Most executable SQL statements can be performed interactively from a terminal using an SQL query manager like BTEQ or Teradata SQL Assistant.

The following types of executable SQL commands cannot be performed interactively:

Cursor control and declaration statements

Dynamic SQL control statements

Stored procedure control statements and condition handlers

Connection control statements

Special forms of SQL statements such as SELECT INTO

These statements can only be used within an embedded SQL or stored procedure application.

Nonexecutable SQL Statements

A nonexecutable SQL statement is one that declares an SQL statement, object, or host or local variable to the preprocessor or stored procedure compiler. Nonexecutable SQL statements are not processed during program execution.

Examples of nonexecutable SQL statements for embedded SQL applications include:

DECLARE CURSOR

BEGIN DECLARE SECTION

END DECLARE SECTION

EXEC SQL

Examples of nonexecutable SQL statements for stored procedures include:

DECLARE CURSOR

DECLARE

SQL Requests

A request to Teradata Database can span any number of input lines. Teradata Database can receive and perform SQL statements that are:

Embedded in a client application program that is written in a procedural language.

Embedded in a stored procedure.

Entered interactively through BTEQ or Teradata SQL Assistant interfaces.

Submitted in a BTEQ script as a batch job.

Submitted through other supported methods (such as CLIv2, ODBC, and JDBC).

Submitted from a C or C++ external stored procedure using CLIv2 or a Java external stored procedure using JDBC.