ExecuteScalar (), executescalar

ExecuteScalar (), executescalar
The ExecuteScalar () method is used to execute a query and return the first column in the first row of the returned result set. All other columns and rows are ignored. If you want to determine whether a piece of data does not exist in the database, you can use this method. // SQL

Private string m_str_variationInfo = @ "SELECT variationinfoMngno
FROM sellersandvariationmngtbl
WHERE sellerCD = @ sellerCD
";

// Process

MySqlParameter [] MySqlParameter = new MySqlParameter [1];
MySqlParameter [0] = new MySqlParameter ("@ sellerCD", prm_sellerCD );

Object val = DataAccess. ExecuteScalar (prm_con, CommandType. Text, m_str_variationInfo, MySqlParameter );

Return val;

If val is null, the read-only data storage does not exist.