Class OrderClause

Namespace: YndigoBlue.Velocity.Model

Assembly: YndigoBlue.Velocity.dll

Represents an ORDER BY clause that specifies how query results should be sorted.

public class OrderClause

Inheritance: object

OrderClause

Examples

Simple ascending sort:

Query query = new Query();
query.AddFromItem(usersTable);
query.AddSelectItem(usersTable["username"]);
query.AddSelectItem(usersTable["created_at"]);

// ORDER BY created_at ASC (default)
query.AddOrderClause(new OrderClause(usersTable["created_at"]));

// SQL: SELECT username, created_at FROM users ORDER BY created_at ASC

Descending sort:

// ORDER BY created_at DESC
query.AddOrderClause(new OrderClause(
    usersTable["created_at"],
    OrderClauseType.Descending
));

// SQL: SELECT username, created_at FROM users ORDER BY created_at DESC

Multi-level sorting:

Query query = new Query();
query.AddFromItem(usersTable);
query.AddSelectItem(usersTable["lastname"]);
query.AddSelectItem(usersTable["firstname"]);
query.AddSelectItem(usersTable["created_at"]);

// ORDER BY lastname ASC, firstname ASC, created_at DESC
query.AddOrderClause(new OrderClause(usersTable["lastname"]));
query.AddOrderClause(new OrderClause(usersTable["firstname"]));
query.AddOrderClause(new OrderClause(
    usersTable["created_at"],
    OrderClauseType.Descending
));

// SQL: SELECT lastname, firstname, created_at FROM users
//      ORDER BY lastname ASC, firstname ASC, created_at DESC

Sorting by expression:

// Create an expression: quantity * price
Expression totalExpression = new Expression("total");
totalExpression.Add(ordersTable["quantity"]);
totalExpression.Add(new ArithmeticOperator(ArithmeticType.Multiply));
totalExpression.Add(ordersTable["price"]);

query.AddSelectItem(totalExpression);

// ORDER BY total DESC
query.AddOrderClause(new OrderClause(
    totalExpression,
    OrderClauseType.Descending
));

// SQL: SELECT quantity * price AS total FROM orders ORDER BY total DESC

Sorting by aggregate function:

Query query = new Query();
query.AddFromItem(ordersTable);
query.AddSelectItem(ordersTable["user_id"]);

Function countFunction = new Function(FunctionType.Count, ordersTable["id"]);
query.AddSelectItem(countFunction);
query.AddGroupClause(ordersTable["user_id"]);

// ORDER BY COUNT(id) DESC
query.AddOrderClause(new OrderClause(
    countFunction,
    OrderClauseType.Descending
));

// SQL: SELECT user_id, COUNT(id) FROM orders
//      GROUP BY user_id ORDER BY COUNT(id) DESC

Remarks

OrderClause defines the sorting behavior for query results. Each clause specifies:

A column, expression, or function to sort by
The sort direction (ascending or descending)

Multiple ORDER BY clauses can be added to a Query to create multi-level sorting. The first clause is the primary sort, subsequent clauses break ties.

Constructors

OrderClause(ISelectItem): Creates a new ORDER BY clause with ascending sort order.

OrderClause(ISelectItem, OrderClauseType): Creates a new ORDER BY clause with specified sort order.

Properties

OrderType: Gets or sets the sort direction (Ascending or Descending).

SelectItem: Gets or sets the column, expression, or function to sort by.

Table of Contents

Class OrderClause

Examples

Remarks

Constructors

Properties