从SQL表中删除具有多个列值的检查

Question

I want to delete a row from an SQL table with multiple column value checking. I know how to do with it a single column value:

SqlConnection connection = new SqlConnection("YourDatabaseConnectionString");

string sqlStatement = "DELETE FROM Customers WHERE ColumnID = @ColumnID";

try{
    connection.Open();
    SqlCommand cmd = new SqlCommand(sqlStatement, connection);
    cmd.Parameters.AddWithValue("@ColumnID", "SomeValueHere");
    cmd.CommandType = CommandType.Text;
    cmd.ExecuteNonQuery();

}
finally {
    connection.Close();
}

However, what is the syntax for multiple column value checking? Also, how should I format the values if they are of Date (SQL) and Time7 (SQL) format?

Answer 1

Add one more clause to the where condition. If you want to delete record which matches both condition, use AND ,and if you want to delete record which matches either one of the condition , then use OR

Query to check both condition

string sqlStatement = "DELETE FROM Customers WHERE
          ColumnID = @ColumnID AND ColumnName2=@SecondValue";

Query to check either one condition

string sqlStatement = "DELETE FROM Customers WHERE 
            ColumnID = @ColumnID OR ColumnName2=@SecondValue";

So your code will be something like this

using(SqlConnection connection = new SqlConnection("YourDatabaseConnectionString"))
{

    string sqlStatement = "DELETE FROM Customers WHERE ColumnID = @ColumnID AND ColumnName2=@SecondValue";
    SqlCommand cmd = new SqlCommand(sqlStatement, connection);
    cmd.CommandType = CommandType.Text;
    cmd.Parameters.AddWithValue("@ColumnID", "SomeValueHere");
    cmd.Parameters.AddWithValue("@SecondValue", "OtherValue");

     try
     {
        connection.Open();
        cmd.ExecuteNonQuery();
     }
     catch(Exception ex)
     {
        //log error
     }    
}