gitee.com/eden-framework/sqlx@v0.0.3/builder/assignment.go (about)

     1  package builder
     2  
     3  import (
     4  	"context"
     5  	"math"
     6  )
     7  
     8  type SqlAssignment interface {
     9  	SqlExpr
    10  	SqlAssignmentMarker
    11  }
    12  
    13  type SqlAssignmentMarker interface {
    14  	asCondition()
    15  }
    16  
    17  func WriteAssignments(e *Ex, assignments ...*Assignment) {
    18  	count := 0
    19  
    20  	for i := range assignments {
    21  		a := assignments[i]
    22  
    23  		if IsNilExpr(a) {
    24  			continue
    25  		}
    26  
    27  		if count > 0 {
    28  			e.WriteString(", ")
    29  		}
    30  
    31  		e.WriteExpr(a)
    32  		count++
    33  	}
    34  }
    35  
    36  func ColumnsAndValues(columnOrColumns SqlExpr, values ...interface{}) *Assignment {
    37  	lenOfColumn := 1
    38  	if canLen, ok := columnOrColumns.(interface{ Len() int }); ok {
    39  		lenOfColumn = canLen.Len()
    40  	}
    41  	return &Assignment{columnOrColumns: columnOrColumns, lenOfColumn: lenOfColumn, values: values}
    42  }
    43  
    44  type Assignments []*Assignment
    45  
    46  type Assignment struct {
    47  	SqlAssignmentMarker
    48  
    49  	columnOrColumns SqlExpr
    50  	lenOfColumn     int
    51  
    52  	values []interface{}
    53  }
    54  
    55  func (a *Assignment) IsNil() bool {
    56  	return a == nil || IsNilExpr(a.columnOrColumns) || len(a.values) == 0
    57  }
    58  
    59  func (a *Assignment) Ex(ctx context.Context) *Ex {
    60  	e := Expr("")
    61  
    62  	useValues := TogglesFromContext(ctx).Is(ToggleUseValues)
    63  
    64  	if useValues {
    65  		e.WriteGroup(func(e *Ex) {
    66  			e.WriteExpr(ExprBy(func(ctx context.Context) *Ex {
    67  				return a.columnOrColumns.Ex(ContextWithToggles(ctx, Toggles{
    68  					ToggleMultiTable: false,
    69  				}))
    70  			}))
    71  		})
    72  
    73  		if len(a.values) == 1 {
    74  			if s, ok := a.values[0].(SelectStatement); ok {
    75  				e.WriteByte(' ')
    76  				e.WriteExpr(s)
    77  				return e.Ex(ctx)
    78  			}
    79  		}
    80  
    81  		e.WriteString(" VALUES ")
    82  
    83  		groupCount := int(math.Round(float64(len(a.values)) / float64(a.lenOfColumn)))
    84  
    85  		for i := 0; i < groupCount; i++ {
    86  			if i > 0 {
    87  				e.WriteByte(',')
    88  			}
    89  
    90  			e.WriteGroup(func(e *Ex) {
    91  				for j := 0; j < a.lenOfColumn; j++ {
    92  					e.WriteHolder(j)
    93  				}
    94  			})
    95  		}
    96  
    97  		e.AppendArgs(a.values...)
    98  
    99  		return e.Ex(ctx)
   100  	}
   101  
   102  	e.WriteExpr(ExprBy(func(ctx context.Context) *Ex {
   103  		return a.columnOrColumns.Ex(ContextWithToggles(ctx, Toggles{
   104  			ToggleMultiTable: false,
   105  		}))
   106  	}))
   107  
   108  	e.WriteString(" = ?")
   109  	e.AppendArgs(a.values[0])
   110  
   111  	return e.Ex(ctx)
   112  }