Varchar without length limit (TLOB)

This section concerns the varchar(max), nvarchar(max), XML(max), longvarchar of MS SQL Server, the text(max) of MySQL, the TLOB of Oracle, and their equivalents in other supported databases.

A longvarchar (TLOB) can be captured as a varchar limited to the length. 

This will allow for manipulating its content in the selection and transformation or as a TLOB without length limit. 

By doing so, it can be replicated without manipulating the content other than an allocation from another TLOB or Null.

The first time a table containing longvarchar is logged, the interface will ask if a maximum length needs to be imposed or not.

If you answer yes, you can specify the max. length with a limit connected to the database engine and its version (i.e., 8,000 for SQL Server 2008 R2) 

It will show the greatest length found in the table.

If you do not wish to limit the length, specify 0 as the value.

Avoid inserting the maximum as a default value (i.e., 8,000) because the length has an impact on the stocking of movements in the log (8,000 characters would be, therefore, automatically used for every single operation).

It has also an impact on the size of the exchanges between the source and the target.

It is important to know that MS SQL Server 2000, 2005, 2008 and 2008R2 queries are currently limited to 16,384 characters of effective data. 

In this example, this column is limited to 8 characters. 

If you need to change the value entered, after having stopped the logging of the table, you need to delete the line related to this column or all the columns in the table DD_MX of the repository. Only the longvarchar type columns are stocked.