检查linq中是否存在列

Question

I have database of external program that I want to connect and operate on through LINQ to SQL. My problem is , I want to support wider range of versions of database, so I have to check for columns if they exists.

I tried something like that:

      IEnumerable<string> k = db.ExecuteQuery<string>("select column_name from INFORMATION_SCHEMA.COLUMNS where COLUMN_NAME='{0}' and TABLE_NAME='POSIEDZENIA'", column);

And it gives me nothing. k.Count() gives error:

The result of a query cannot be enumerated more than once

When I cast it to List by ToList() it gives 0 count.

I'm sure that this column exists in database that datacontext is connected to.

Have you any suggestions?

Answer 1

Just remove quotation around parameter ( {0} ).

IEnumerable<string> k = db.ExecuteQuery<string>("select column_name from 
INFORMATION_SCHEMA.COLUMNS where COLUMN_NAME={0} and TABLE_NAME='POSIEDZENIA'", column);

for more information visit this msdn article .