Sybase 12.4.2 manual How Adaptive Server IQ makes connections, Steps in establishing a connection

CHAPTER 2 Running Adaptive Server IQ

How Adaptive Server IQ makes connections

Who needs to read this section?

This section describes how the interface libraries establish connections.

In many cases, establishing a connection to a database is straightforward using the information presented in the preceding sections of this chapter. However, if you are having problems establishing connections to a server, you may need to understand how Adaptive Server IQ establishes connections in order to resolve your problems.

Note If you have no problem establishing connections to your database, you do not need to read this section.

The software follows exactly the same procedure for each of the following types of client application:

•Any ODBC application using the SQLDriverConnect function, which is the common method of connection for ODBC applications. Many application development systems, such as Sybase PowerBuilder and Power++, belong to this class of application.

•Any client application using Embedded SQL and using the recommended function for connecting to a database (db_string_connect).

The SQL CONNECT statement is available for Embedded SQL applications and in Interactive SQL. It has two forms: CONNECT AS... and CONNECT USING... . All the database administration tools, including utilities and Interactive SQL, use db_string_connect.

Steps in establishing a connection

To establish a connection to Adaptive Server IQ, the client application carries out the following steps:

1Locate the interface library. The client application must locate the ODBC driver or Embedded SQL interface library.

2Assemble a list of connection parameters. Connection parameters may be provided in several places, such as data sources, a connection string assembled by the application, and an environment variable. The ODBC driver or Embedded SQL interface library assembles the parameters into a single list.

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