如何使用asp.net获取SQL Server外键中的数据？

Question

This question is somewhat similar and related to my previous question How to get data in an sql foreign key using asp.net entity framework? so I will be using the same SQL Server tables.

This time, instead of accessing the foreign key value through Entity Framework, I want to know how to do it in a regular SQL script like this (take note, the script that I'm talking about is inside the string.Format ):

public static void getRowNumber(string brand)
{
    string query = string.Format("SELECT COUNT(*) FROM stringInstrumentItem WHERE brandId LIKE @brand");

    conn1.Open();

    command1.CommandText = query;
    command1.Parameters.Add(new SqlParameter("brand", brand));

    Int32 count = (Int32)command1.ExecuteScalar();

    conn1.Close();

    command1.Parameters.Clear();

    AddASPXAndCSFile.X = count;
}

Just to recap, I have two SQL Server tables called stringInstrumentItem and brand . I created the foreign key in the table stringInstrumentItem referring to the primary key of the table brand . So I'm attempting to access the column name in table brand through stringInstrumentItem .

As you can see, I'm attempting to access the value in table brand through brandId , which does not work.

Hope you guys can help me on this one. Cheers!

Answer 1

If I understand your question correctly, it seems like a simple query -

SELECT COUNT(*) FROM stringInstrumentItem 
WHERE brandId IN (SELECT brandId FROM brand WHERE name LIKE @brand)

Please make use you have @ and % (based on your requirement) .

command1.Parameters.Add(new SqlParameter("@brand", "%" + brand + "%"));