# DD\_for\_SQLServer registry subkey

For each given instance of an MS SQL Server server for which Talend Change Data Capture for MS SQL Server Source has been installed, you get a key below the DD\_for\_SQLServer key. Its name will be the MS SQL Server instance name.

For example, if you install or add Talend Change Data Capture for an MS SQL Server instance named TCDC\_DEV\_DEV2 or DEV2\TCDC\_DEV\_DEV2 (meaning TCDC\_DEV\_DEV2 instance on the DEV2 server), you will get a subkey named TCDC\_DEV\_DEV2.

In this subkey, the following parameters will be applicable for this SQL Server instance:

| Parameter | Description |
| --- | --- |
| **DriverName** | This parameter contains the ODBC driver name used to access the<br>MS SQL Server base. The default value is SQL<br>Server. |
| LobManagement | Used with an MS Azure SQL source to manage large objects.<br><br><ul> <li>value = <kbd>0</kbd> (default value) means LOBS                                        are not managed</li> <li>value = <kbd>1</kbd> means BLOBs are considered                                        as NULL columns</li> <li>value = <kbd>2</kbd> means BLOBs are considered                                        as empty columns</li> </ul> |
| **Maxtrans** | Used with an MS Azure SQL source to stop the capture of a table<br><br>and move on to the next table.<br><br><ul> <li>value =<kbd>0</kbd> means no limit is set.                                            Tables are captured one by one.</li> <li>value =<kbd>1</kbd> or more means the                                            captured rows of a table are limited to the value                                            entered.</li> </ul> |
| **ParamPwd** | This parameter is only available if the MS SQL Server is on 7.0<br>version or if the SQL instance for an MS SQL 2000 Server is not<br>a named instance. Its value is taken into account by the unnamed<br>instance (SQL 2000) or by the 7.0 MS SQL Server.<br><br>This parameter indicates the MS SQL Server password associated<br>with the username (ParamUid parameter<br>described above) that will be used by the manager, the<br>scheduler, the supervisor and the source engine to establish the<br>connection to MS SQL Server.<br><br>The default value is the one provided after the installation (see<br>[Installing MS SQL Server<br>source](https://help.qlik.com/talend/r/en-US/7.3/change-data-capture-installation-guide/installing-sql-server-source)). |
| **ParamUid** | This parameter is only available if the MS SQL Server is on 7.0<br><br>version or if the SQL instance for an MS SQL 2000 Server is not<br>a named instance. Its value is taken into account by the unnamed<br>instance (SQL 2000) or by the 7.0 MS SQL Server. This parameter<br>specifies the username that will be used by the manager, the<br>scheduler, the supervisor and the source engine to establish the<br>connection to MS SQL Server.<br><br>The default value is the value provided after the installation<br>(see [Installing MS SQL Server source](https://help.qlik.com/talend/en-US/change-data-capture-installation-guide/7.3/installing-sql-server-source)). |
| **TextMaxLength** | This parameter exists only if the MS SQL Server is on 7.0 version<br>or if the SQL instance for an SQL 2000 server is not a named<br>instance.<br><br>Its value contains the maximal length for a text area in case no<br>details are provided in the DD\_MX table provided during the<br>parameter definition. This information is usually not used.<br><br>Its value is included by the unnamed instance (SQL 2000) or by<br>the 7.0 MS SQL Server.<br><br>The default value is set to 1000<br>characters. |
| Unicode | This parameter is used with an MS Azure SQL source to keep the<br>Unicode values.<br><br>This key activates and deactivates the Unicode<br>parameter, which manages nvarchar data type columns:<br><br><ul> <li>value= <kbd>0</kbd> (default value) means                                            the Unicode is not activated: characters are converted                                            to ANSI 1 byte. Unicode values are not kept; only                                            nvarchar columns are kept.</li> <li>value= <kbd>1</kbd> means the Unicode is                                            activated: nvachar are stored on 2 bytes in the                                            journal.The total length of the nvarchar table is                                                doubled.<div><span>Information note</span><span>Note:</span> Issues may arise in the following                                                case: after performing replications with Unicode =                                                  <kbd>0</kbd>, you decide to change the                                                value to <kbd>1</kbd>. Before changing                                                the value, contact Talend <a href="https://www.talend.com/technical-support/?_ga=2.177601517.935794220.1683617077-857954988.1641206411" target="_blank">Support</a>                                                team.</div> </li> </ul> |
| UseAlias | This parameter is automatically activated (default is set to<br>1) when an MS Azure Managed Instance for<br>SQL source has been installed. See [Installing MS Azure SQL Managed<br>Instance source](https://help.qlik.com/talend/r/en-US/7.3/change-data-capture-installation-guide/installing-ms-azure-mi-sql-source) for more details.<br><br>Set the parameter to<br>0 if you want to stop using this<br>source. |
| UseCDC | This parameter is automatically activated (default is set to<br>1) when an MS Azure SQL source has been<br>installed.<br><br>Set the parameter to 0 if<br>you want to stop using this source. |
| **WaitBeforeLog** | This parameter configures the duration of the break between MS<br>SQL Server calls. |