Text fields in SQL Server queries are returned as empty

There was a strange phenomenon in maintaining the system data last night. Clearly the database has data, the query result is returned to empty. This is the case, query the working table about the job description, the Chinese content to match the job Description field, where the matching content contains spaces.

Try to remove the contents after the first space and the query has the result. Plus one more space is gone. Either "=" or "like" match, there is no result.

Then, look at the Job Description field type, which is the nvarchar type. Remember, add n before the matching character.

SQL statement: SELECT * from the Weekday log table where job Description field =n ' content is customer fill in there is a space before, resulting in a null return result. Write n before matching field can be solved. ‘

Text fields in SQL Server queries are returned as empty