Characteristics of Sybase Open Client and jConnect connections

When SQL Anywhere is serving applications over TDS, it automatically sets relevant database options to values compatible with Adaptive Server Enterprise default behavior. These options are set temporarily, for the duration of the connection only. The client application can override them at any time.

Default settings

The database options set on connection using TDS include:

Option	Set to
allow_nulls_by_default	Off
ansi_blanks	On
ansinull	Off
chained	Off
close_on_endtrans	Off
date_format	YYYY-MM-DD
date_order	MDY
escape_character	Off
isolation_level	1
on_tsql_error	Continue
quoted_identifier	Off
time_format	HH:NN:SS.SSS
timestamp_format	YYYY-MM-DD HH:NN:SS.SSS
tsql_variables	On

How the startup options are set

The default database options are set for TDS connections using a system procedure named sp_tsql_environment. This procedure sets the following options:

SET TEMPORARY OPTION allow_nulls_by_default='Off';
SET TEMPORARY OPTION ansi_blanks='On';
SET TEMPORARY OPTION ansinull='Off';
SET TEMPORARY OPTION chained='Off';
SET TEMPORARY OPTION close_on_endtrans='Off';
SET TEMPORARY OPTION date_format='YYYY-MM-DD';
SET TEMPORARY OPTION date_order='MDY';
SET TEMPORARY OPTION escape_character='Off';
SET TEMPORARY OPTION isolation_level='1';
SET TEMPORARY OPTION on_tsql_error='Continue';
SET TEMPORARY OPTION quoted_identifier='Off';
SET TEMPORARY OPTION time_format='HH:NN:SS.SSS';
SET TEMPORARY OPTION timestamp_format='YYYY-MM-DD HH:NN:SS.SSS';
SET TEMPORARY OPTION tsql_variables='On';

Do not edit the sp_tsql_environment procedure

Do not alter the sp_tsql_environment procedure yourself. It is for system use only.

The procedure sets options only for connections that use the TDS communications protocol. This includes Sybase Open Client and JDBC connections using jConnect. Other connections (ODBC and embedded SQL) have the default settings for the database.

You can change the options for TDS connections.

♦ To change the option settings for TDS connections

Create a procedure that sets the database options you want. For example, you could use a procedure such as the following:

CREATE PROCEDURE my_startup_procedure()
BEGIN
  IF CONNECTION_PROPERTY('CommProtocol')='TDS' THEN
    SET TEMPORARY OPTION quoted_identifier='Off';
  END IF
END;

This particular procedure example changes only the quoted_identifier option from the default setting.

Set the login_procedure option to the name of a new procedure:
SET OPTION login_procedure= 'DBA.my_startup_procedure';

Future connections will use the procedure. You can configure the procedure differently for different user IDs.

For more information about database options, see Database options.

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