github.com/eden-framework/sqlx@v0.0.2/builder/stmt_select.go (about)

     1  package builder
     2  
     3  import (
     4  	"context"
     5  )
     6  
     7  type SelectStatement interface {
     8  	SqlExpr
     9  	selectStatement()
    10  }
    11  
    12  func Select(sqlExpr SqlExpr, modifiers ...string) *StmtSelect {
    13  	return &StmtSelect{
    14  		sqlExpr:   sqlExpr,
    15  		modifiers: modifiers,
    16  	}
    17  }
    18  
    19  type StmtSelect struct {
    20  	SelectStatement
    21  	sqlExpr   SqlExpr
    22  	table     *Table
    23  	modifiers []string
    24  	additions []Addition
    25  }
    26  
    27  func (s *StmtSelect) IsNil() bool {
    28  	return s == nil
    29  }
    30  
    31  func (s StmtSelect) From(table *Table, additions ...Addition) *StmtSelect {
    32  	s.table = table
    33  	s.additions = additions
    34  	return &s
    35  }
    36  
    37  func (s *StmtSelect) Ex(ctx context.Context) *Ex {
    38  	multiTable := false
    39  
    40  	for i := range s.additions {
    41  		addition := s.additions[i]
    42  		if IsNilExpr(addition) {
    43  			continue
    44  		}
    45  
    46  		if addition.AdditionType() == AdditionJoin {
    47  			multiTable = true
    48  		}
    49  	}
    50  
    51  	if multiTable {
    52  		ctx = ContextWithToggles(ctx, Toggles{
    53  			ToggleMultiTable: multiTable,
    54  		})
    55  	}
    56  
    57  	e := Expr("SELECT")
    58  
    59  	if len(s.modifiers) > 0 {
    60  		for i := range s.modifiers {
    61  			e.WriteByte(' ')
    62  			e.WriteString(s.modifiers[i])
    63  		}
    64  	}
    65  
    66  	sqlExpr := s.sqlExpr
    67  
    68  	if IsNilExpr(sqlExpr) {
    69  		sqlExpr = Expr("*")
    70  	}
    71  
    72  	e.WriteByte(' ')
    73  	e.WriteExpr(sqlExpr)
    74  
    75  	if !IsNilExpr(s.table) {
    76  		e.WriteString(" FROM ")
    77  		e.WriteExpr(s.table)
    78  	}
    79  
    80  	WriteAdditions(e, s.additions...)
    81  
    82  	return e.Ex(ctx)
    83  }
    84  
    85  func ForUpdate() *OtherAddition {
    86  	return AsAddition(Expr("FOR UPDATE"))
    87  }