/// <summary>
/// Joins two tables using on an arbitrary join condition
/// </summary>
/// <param name="type">The type of join to be created.</param>
/// <param name="leftTable">The left table</param>
/// <param name="rightTable">The right table</param>
/// <param name="conditions">Specifies how the join should be performed</param>
/// <remarks>
/// Use this overload to create complex join conditions.
/// Note that not all <see cref="WhereClause"/> operators and expressions are supported in joins.
/// </remarks>
/// <example>
/// WhereClause condition = new WhereClause(WhereClauseRelationship.Or);
/// condition.Terms.Add(WhereTerm.CreateCompare(SqlExpression.Field("productId", tOrders), SqlExpression.Field("productId", tProducts), CompareOperator.Equal));
/// condition.Terms.Add(WhereTerm.CreateCompare(SqlExpression.Field("productName", tOrders), SqlExpression.Field("productName", tProducts), CompareOperator.Equal));
/// query.FromClause.Join(JoinType.Left, tOrders, tProducts, condition);
/// </example>
public void Join(JoinType type, FromTerm leftTable, FromTerm rightTable, WhereClause conditions)
{
if (conditions.IsEmpty && type != JoinType.Cross)
{
throw new InvalidQueryException("A join must have at least one condition.");
}
joins.Add(new Join(leftTable, rightTable, conditions, type));
}
