SQL Server使用PHP将列名截断为29个字符

Question

I have a SQL Server query that I take the result from and insert into an array like

while($row = mssql_fetch_array($res, MSSQL_ASSOC)) { ... }

Now, the problem is that looking at the $row I see that the column named customer_social_sequrity_number becomes the key customer_social_sequrity_numbe. All other keys seems to be trunkated to 29 characters to. Is this a limit? I can't find any information about such a limit.

This is a bit of a drag since I'm importing data from a 3rd party database and use the key of the array to mapp the data to an object.

Does not seem to be a limitation on the PHP side as stated. Is it possibly some limitation on the SQL Server part? Running the query using MS Query Analyzer it seems fine.

Answer 1

I found the answer to the question. It seems like in Windows, Microsoft's DBLIB is used and functions that return a column name are based on the dbcolname() function in DBLIB. DBLIB was apperently developed for SQL Server 6 where the max length of a columnname was 30. For this reason, the maximum column length is 30 characters.

Here you can get a version of FreeTDS for Windows that hopefully eliviates this problem: http://docs.moodle.org/en/Installing_MSSQL_for_PHP#Using_FreeTDS_on_Windows

Also on Linux this will not be a problem it only affects Windows