Updating a row in a table

Placeholders for parameters in SQL statements are indicated by the ? character. For any INSERT, UPDATE, or DELETE, each ? is referenced according to its ordinal position in the command's parameters collection. For example, the first ? is referred to as 0, and the second as 1.

Prérequis

There are no prerequisites for this task.

Task

Declare a ULCommand.
ULCommand cmd;

Assign a statement to the ULCommand object.

cmd = conn.CreateCommand();
cmd.CommandText = "UPDATE MyTable SET MyColumn1 = ? WHERE MyColumn2 = ?";

Assign input parameter values for the statement.

String newValue;
String oldValue;

cmd.Parameters.Clear();

// assign values
cmd.Parameters.Add("", newValue);
cmd.Parameters.Add("", oldValue);

Execute the statement.

int rowsUpdated = cmd.ExecuteNonQuery();

If you are using explicit transactions, commit the change.
myTransaction.Commit();

Résultat

Row entries from MyTable are updated where the MyColumn1 value is an empty string. In this scenario, the MyColumn2 value is also set to an empty string.

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