ExecuteScalar

public object ExecuteScalar(string query)

Executes a query without parameters, and returns the first column of the first row in the result set returned by the query. Additional columns or rows are ignored.

Parameters :

query - a string that represent the sql select query without parameters.

Return :

A castable object that represent the first column of the first row in the result set returned by the query

You will probably need to cast the object before use.

Throw :

InvalidOperationException, if the connection isn't opened.

public object ExecuteScalar(string query, params string[] sqlParameters)

Executes a query with parameters, and returns the first column of the first row in the result set returned by the query. Additional columns or rows are ignored.

Parameters :

query - a string that represent the sql_select_query with parameters. sqlParameters - One to many pairs of strings, parameter's name first followed by the value. (E.g.: "param1", "value1", "param2", "value2"...).

Notice : Be sure to always write pairs of strings, or it won't work.

E.g:

string ProductName = (string)sql.ExecuteScalar("select Name from table where id = @id", "id", "12")

Return :

A castable object that represent the first column of the first row in the result set returned by the query

You will probably need to cast the object before use.

Throw :

InvalidOperationException, if the connection isn't opened.

ArgumentException, if the number of parameters isn't even