Method UpdateRecords

Namespace

YndigoBlue.Velocity.Engine

Assembly

YndigoBlue.Velocity.dll

UpdateRecords(Update)

Updates one or more records in a table based on specified criteria.

public int UpdateRecords(Update update)

Parameters

update Update

An Update object defining which records to update and what values to set.

Returns

int

The number of rows that matched the WHERE clause and were modified.

Examples

using (var m = new Manager(conn))
{
    var schema = m.LoadSchema("app");
    var usersTable = schema["users"];

    // Create an update operation
    var update = new Update(usersTable);
    update.SetFieldDateTime("last_login", DateTime.Now);
    update.AddWhereClause(new Criterion<string>(usersTable["email"], "john@example.com"));

    int rowsUpdated = m.UpdateRecords(update);
    Console.WriteLine($"Updated {rowsUpdated} rows");
}

Remarks

The returned row count is what makes compare-and-swap possible: pair a guard condition in the WHERE clause with SetFieldAsExpression(ISelectItem, Expression) and a return of 0 tells you the guard failed and nothing was written, without any read-then-write race.

Exceptions

DbException

Thrown when a database error occurs.