Correct mapping of big Visual FoxPro CHAR column to the appropriate SQL Server data type

Question

I am migrating a Visual FoxPro database to SQL Server. One of the tables has a Char column with length 2147483647. I am wondering if the correct data type to use in SQL Server 2008 R2 is Char(2147483647). Is there an alternative type I can use in SQL Server which will not result in any loss of information?

The following image gives a description of the column as shown within Visual Studio 2008.

Answer 1

Visual FoxPro's native CHAR type only allows up to about 255 characters. What you're seeing is a FoxPro MEMO field, translated to a generic OLE equivalent.

A SQL Server VARCHAR(MAX) is the usual proper equivalent, assuming the MEMO is simply user-entered text in a western dialect and not a multi-linqual or data-blob variation.

Be aware that FoxPro does NOT speak UTF natively, so you may have code-page translation issues.

Answer 2

Hope this helps someone else.

MSDN varchar description states:

Use varchar(max) when the sizes of the column data entries vary considerably, and the size might exceed 8,000 bytes.

The maximum storage for Char is 8000 bytes/characters. varchar(max) on the other hand will use a storage size equal to the actual length of the characters entered plus 2 bytes.