github.com/kunlun-qilian/sqlx/v2@v2.24.0/builder/addition_order_by.go (about)

     1  package builder
     2  
     3  import (
     4  	"context"
     5  )
     6  
     7  type OrderByAddition struct {
     8  }
     9  
    10  func (OrderByAddition) AdditionType() AdditionType {
    11  	return AdditionOrderBy
    12  }
    13  
    14  func OrderBy(orders ...*Order) *orderBy {
    15  	finalOrders := make([]*Order, 0)
    16  
    17  	for i := range orders {
    18  		if IsNilExpr(orders[i]) {
    19  			continue
    20  		}
    21  		finalOrders = append(finalOrders, orders[i])
    22  	}
    23  
    24  	return &orderBy{
    25  		orders: finalOrders,
    26  	}
    27  }
    28  
    29  var _ Addition = (*orderBy)(nil)
    30  
    31  type orderBy struct {
    32  	OrderByAddition
    33  	orders []*Order
    34  }
    35  
    36  func (o *orderBy) IsNil() bool {
    37  	return o == nil || len(o.orders) == 0
    38  }
    39  
    40  func (o *orderBy) Ex(ctx context.Context) *Ex {
    41  	e := Expr("ORDER BY ")
    42  	for i := range o.orders {
    43  		if i > 0 {
    44  			e.WriteQueryByte(',')
    45  		}
    46  		e.WriteExpr(o.orders[i])
    47  	}
    48  	return e.Ex(ctx)
    49  }
    50  
    51  func AscOrder(target SqlExpr) *Order {
    52  	return &Order{target: target, typ: "ASC"}
    53  }
    54  
    55  func DescOrder(target SqlExpr) *Order {
    56  	return &Order{target: target, typ: "DESC"}
    57  }
    58  
    59  var _ SqlExpr = (*Order)(nil)
    60  
    61  type Order struct {
    62  	target SqlExpr
    63  	typ    string
    64  }
    65  
    66  func (o *Order) IsNil() bool {
    67  	return o == nil || IsNilExpr(o.target)
    68  }
    69  
    70  func (o *Order) Ex(ctx context.Context) *Ex {
    71  	e := Expr("")
    72  	e.Grow(1)
    73  
    74  	e.WriteGroup(func(e *Ex) {
    75  		e.WriteExpr(o.target)
    76  	})
    77  
    78  	if o.typ != "" {
    79  		e.WriteQueryByte(' ')
    80  		e.WriteQuery(o.typ)
    81  	}
    82  
    83  	return e.Ex(ctx)
    84  }