DbVar is a position-dependent config.txt directive that is part of a database definition and appears anywhere before a Title line. DbVar is used to associate a text string with a database definition. This text string can be incorporated into the text recorded by LogFormat and LogSPU log files.
If DbVar appears by itself, it clears all values in the ten variables. To set a variable, use DbVar followed immediately by a single digit 0 through 9, a space, then an arbitrary text string. These directives should appear before the Title line of the database definition that are meant to affect. These values span multiple database definitions until changed or reset.
DbVar
DbVar0 General Database DbVar1 Funded by Some Consortium
Title Some Database URL http://www.somedb.com/ Domain somedb.com
Title Other Database URL http://www.otherdb.com/ Domain otherdb.com
DbVar0 Legal Database DbVar1 Funded by Law College
Title Another Database URL http://www.otherdb.com/ Domain otherdb.com
In a LogFormat, you can use %{ezproxy-dbvar0} to access the DbVar0 text and %{ezproxy-dbvar1} to access the DbVar1 text.