# Using Babelfish product version parameter
<a name="babelfish-guc-version"></a>

 A new Grand Unified Configuration (GUC) parameter called `babelfishpg_tds.product_version` is introduced from Babelfish 2.4.0 and 3.1.0 versions. This parameter allows you to set the SQL Server product version number as the output of Babelfish. 

The parameter is a 4-part version ID string, and each part should be separated by “.”. 

Syntax  

```
Major.Minor.Build.Revision
```
+ Major Version: A number between 11 and 16.
+ Minor Version: A number between 0 and 255. 
+ Build Version: A number between 0 and 65535.
+ Revision: 0 and any positive number.

## Configuring Babelfish product version parameter
<a name="babelfish-guc-version-setvalues"></a>

You must use the cluster parameter group to set the babelfishpg\$1tds.product\$1version parameter in the console. For more information on how to modify the DB cluster parameter, see [Modifying parameters in a DB cluster parameter groupin Amazon Aurora](USER_WorkingWithParamGroups.ModifyingCluster.md).

When you set the product version parameter to an invalid value, the change will not take effect. Although the console might show you the new value, the parameter retains the previous value. Check the engine log file for details about the error messages. 

For Linux, macOS, or Unix:

```
aws rds modify-db-cluster-parameter-group \
--db-cluster-parameter-group-name mydbparametergroup \
--parameters "ParameterName=babelfishpg_tds.product_version,ParameterValue=15.2.4000.1,ApplyMethod=immediate"
```

For Windows:

```
aws rds modify-db-cluster-parameter-group ^
--db-cluster-parameter-group-name mydbparametergroup ^
--parameters "ParameterName=babelfishpg_tds.product_version,ParameterValue=15.2.4000.1,ApplyMethod=immediate"
```

## Affected queries and parameter
<a name="babelfish-guc-version-affects"></a>


|  Query/Parameter  |  Result  |  Effective time  | 
| --- | --- | --- | 
|   SELECT @@VERSION   |   Returns user defined SQL Server version (babelfishpg\$1tsql.version value = Default)   |   Immediately   | 
|   SELECT SERVERPROPERTY('ProductVersion')   |   Returns user defined SQL Server version   |   Immediately   | 
|   SELECT SERVERPROPERTY('ProductMajorVersion')   |   Returns Major Version of the user defined SQL Server version   |   Immediately   | 
|   VERSION tokens in PRELOGIN Response Message   |   Server returns PRELOGIN messages with user defined SQL Server version   |   Takes effect when a user creates a new session   | 
|   SQLServerVersion in LoginAck when using JDBC   |   DatabaseMetaData.getDatabaseProductVersion() returns user defined SQL Server version   |   Takes effect when a user creates a new session   | 

## Interface with babelfishpg\$1tsql.version parameter
<a name="babelfish-guc-version-tsql"></a>

You can set the output of the @@VERSION using the parameters babelfishpg\$1tsql.version and babelfishpg\$1tds.product\$1version. The following examples show how these two parameters interface.
+ When babelfishpg\$1tsql.version parameter is "default" and babelfishpg\$1tds.product\$1version is 15.0.2000.8.
  +  Output of @@version – 15.0.2000.8.
+ When babelfishpg\$1tsql.version parameter is set to 13.0.2000.8 and babelfishpg\$1tds.product\$1version parameter is 15.0.2000.8.
  + Output of @@version – 13.0.2000.8.