Problem executing query for SQL Server in C# with SQLDataReader

Question

I am trying to execute a query in C# using SqlDataReader but I receive an error message from the database, " Incorrect syntax near '.' ".

I am not sure what is wrong with my SQL query. I can execute it perfectly fine in SQL Server Management Studio.

try
{
   SqlConnection thisConnection = new SqlConnection();
   thisConnection.Open();
   SqlCommand thisCommand = thisConnection.CreateCommand();
   thisCommand.CommandText = "SELECT"
                +"db.name DBName,"
                +"tl.request_session_id,"
                +"wt.blocking_session_id,"
                +"OBJECT_NAME(p.OBJECT_ID) BlockedObjectName,"
                +"tl.resource_type,"
                +"h1.TEXT AS RequestingText,"
                +"h2.TEXT AS BlockingText,"
                +"tl.request_mode"
                +"FROM sys.dm_tran_locks AS tl"
                +"INNER JOIN sys.databases db ON db.database_id = tl.resource_database_id"
                +"INNER JOIN sys.dm_os_waiting_tasks AS wt ON tl.lock_owner_address = wt.resource_address"
                +"INNER JOIN sys.partitions AS p ON p.hobt_id = tl.resource_associated_entity_id"
                +"INNER JOIN sys.dm_exec_connections ec1 ON ec1.session_id = tl.request_session_id"
                +"INNER JOIN sys.dm_exec_connections ec2 ON ec2.session_id = wt.blocking_session_id"
                +"CROSS APPLY sys.dm_exec_sql_text(ec1.most_recent_sql_handle) AS h1"
                +"CROSS APPLY sys.dm_exec_sql_text(ec2.most_recent_sql_handle) AS h2";

   SqlDataReader thisReader = thisCommand.ExecuteReader();
   while (thisReader.Read())
   {
      Console.WriteLine("\t{0}\t{1}", thisReader["DBName"], thisReader["BlockedObjectName"]);
   }
   thisReader.Close();
   thisConnection.Close();
}
catch (SqlException e)
{
   Console.WriteLine(e.Message);
}

Answer 1

You need spaces at the end of some of the lines you are concatenating:

For example:

            +"tl.request_mode"
            +"FROM sys.dm_tran_locks AS tl"

Will create the SQL

 ...tl.request_modeFROM sys.dm_tran_locks AS tl...

Change it to

            +"tl.request_mode " 
            +"FROM sys.dm_tran_locks AS tl"

There are also a few other lines with the same problem.

This is a good example of why it is important to actually print out the concatenated string when testing a dynamically built SQL string instead of just pasting the code and editing out the quotes and + signs.

Answer 2

As John mentioned you need spaces at the end of your lines as you are missing a few.

As an example your initial error is coming from the first two lines

thisCommand.CommandText = "SELECT" 
                +"db.name DBName," 

which will equal

SELECTdb.name DBName,

Thats where the " Incorrect syntax near '.'" is coming from as db. is being added onto the SELECT statement.

Answer 3

JohnFx and kevchadders are right that the error is due to the resulting string not having appropriate whitespace. As for what you can do about it - if you'd like the query to remain more or less in the same format, you can use @-quoting:

thisCommand.CommandText = 
@"SELECT
    db.name DBName,
    tl.request_session_id,
    wt.blocking_session_id,
    OBJECT_NAME(p.OBJECT_ID) BlockedObjectName,
    tl.resource_type,
    h1.TEXT AS RequestingText,
    h2.TEXT AS BlockingText,
    tl.request_mode
FROM sys.dm_tran_locks AS tl
INNER JOIN sys.databases db ON db.database_id = tl.resource_database_id
INNER JOIN sys.dm_os_waiting_tasks AS wt ON tl.lock_owner_address = wt.resource_address
INNER JOIN sys.partitions AS p ON p.hobt_id = tl.resource_associated_entity_id
INNER JOIN sys.dm_exec_connections ec1 ON ec1.session_id = tl.request_session_id
INNER JOIN sys.dm_exec_connections ec2 ON ec2.session_id = wt.blocking_session_id
CROSS APPLY sys.dm_exec_sql_text(ec1.most_recent_sql_handle) AS h1
CROSS APPLY sys.dm_exec_sql_text(ec2.most_recent_sql_handle) AS h2
";

SqlDataReader thisReader = thisCommand.ExecuteReader();

This will respect your line ends and other whitespace so you get to have a readable query you can easily copy-paste from the C# into SSMS, without the whitespace errors, without concatenation, and without all the StringBuilder.Append statements.