Creating variable value files (AccessToSQL)

A variable value file is an XML file comprising the parameter values of commands (such as the source or destination server name) that frequently change across server migrations. When a large number of database migrations occur, multiple variable files for storing the value of each source server are created and referenced in a master script file with the -v switch at command line. This behavior helps in maintaining static values in a few script files with the variable values in multiple variable files.

The following conditions apply:

• Variable names are prefixed and suffixed with a $ (dollar) symbol. If a variable isn't assigned a value in the variable value file, an error during the parsing of the script file occurs, resulting in stalling the console execution process.

• The escape character for $ is $$. If the value of a variable or static value of a parameter contains a $ (dollar) symbol, then $$ must be specified to treat it as a character instead of a variable.

• For maintainability purposes, variables can be declared inside 'variable-group' elements for logical separation of user-defined variables. Usage of this element isn't mandatory.

Examples

Example 1

Sample of variable value file commands:

<variables>
  <variable-group name="ProjectSpecs">
    <variable name="$type$" value="MyProject"/>
    <variable name="$project_folder$" value=".\$project_name$"/>
    <variable name="$project_name$" value="$type$ConsoleProject"/>
    <variable name="$project_overwrite$" value="true"/>
    <variable name="$project_type$" value="sql-server-2016"/>
  </variable-group>
</variables>

Example 2

Sample of variable value file commands:

<variables>
  <variable-group name="SQLServerParams">
    <variable-group name="SqlServerConnectionParams">
      <variable name="$TargetServerName$" value="xxx"/>
      <variable name="$TargetDB$" value="xxx"/>
      <variable name="$TargetUserName$" value="xxx"/>
      <variable name="$TargetPassword$" value="xxx"/>
      <variable name="$TargetIsTrusted$" value="xxx"/>
      <variable name="$TrustedConnection$" value="xxx"/>
    </variable-group>
    <variable-group name="SqlServerObjectParams">
      <variable name="$ObjectName1$" value="TestTable1"/>
      <variable name="$ObjectName2$" value="TestProc1"/>
    </variable-group>
  </variable-group>
</variables>

Variable value file validation

The user can easily validate their variable value file against the schema definition file ConsoleScriptVariablesSchema.xsd available in the Schemas folder.

Related content

• Creating the server connection files