Sybase 12.4.2 manual Connection parameter priorities, Specify database files using DBF

Connection parameters

•The entries in a connection string are read left to right. If the same parameter is specified more than once, the last one in the string applies.

•If a string contains a DSN or FILEDSN entry, the profile is read from the configuration file, and the entries from the file are used if they are not already set. For example, if a connection string contains a data source name and sets some of the parameters contained in the data source explicitly, then in case of conflict the explicit parameters are used.

Connection parameter priorities

Connection parameters often provide more than one way of accomplishing a given task. This is particularly the case with embedded databases, where a database server is started by the connection string.

For example, if your connection starts a database, you can specify the database name using the DBN connection parameter or using the DBS parameter.

Here are some recommendations and notes for situations where connection parameters conflict:

•	Specify database files using DBF	You can specify a database file on
	the Start parameter or using the DBF parameter. DBF is recommended.
•	Specify database names using DBN	You can specify a database
	name on the Start parameter, the DBS parameter, or using the DBN
	parameter. DBN is recommended.
•	Use the Start parameter to specify cache size		Even though you

use the DBF connection parameter to specify a database file, you may still want to tune the way in which it starts. You can use the Start parameter to do this.

For example, if you are using the Java features of Adaptive Server IQ, you should provide additional cache memory for the Catalog Store on the Start parameter. The following sample set of embedded database connection parameters describes a connection that may use Java features:

DBF=path\asademo.db

DBN=Sample

ENG=Sample Server

UID=DBA

PWD=SQL

Start=asiqsrv12 -c 8M

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