-
Notifications
You must be signed in to change notification settings - Fork 0
/
select.go
150 lines (125 loc) · 2.78 KB
/
select.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
package jdb
import (
"bytes"
"context"
"strconv"
)
type SelectBuilder struct {
q *Query
wb *WhereBuilder
columns []SelectField
limit uint64
limitDefined bool
offset uint64
offsetDefined bool
order []Order
}
type selectCount struct{}
var defaultSelectColumns = []SelectField{
kindField, idField, parentKindField, parentIdField, dataField, createTimeField, updateTimeField}
func (sc selectCount) toSelectField() string {
return "count(*) AS count"
}
func newSelectBuilder(q *Query, wb *WhereBuilder, columns []SelectField) *SelectBuilder {
if wb == nil {
wb = newWhereBuilder(q)
}
return &SelectBuilder{q: q, wb: wb, columns: columns}
}
func (b *SelectBuilder) Limit(v uint64) *SelectBuilder {
if b.limit == v {
return b
}
n := *b
n.limit = v
n.limitDefined = true
return &n
}
func (b *SelectBuilder) Offset(v uint64) *SelectBuilder {
if b.offset == v {
return b
}
n := *b
n.offset = v
n.offsetDefined = true
return &n
}
func (b *SelectBuilder) OrderBy(order ...Order) *SelectBuilder {
if len(order) == 0 {
return b
}
n := *b
if len(b.order) == 0 {
n.order = order
return &n
}
total := len(b.order) + len(order)
tmp := make([]Order, total)
start := copy(tmp, b.order)
for i, v := range order {
tmp[i+start] = v
}
n.order = tmp
return &n
}
func (b *SelectBuilder) ToSQL() (string, []interface{}, error) {
var params []interface{}
query := &bytes.Buffer{}
query.WriteString("SELECT ")
for i, c := range b.columns {
if i != 0 {
query.WriteString(", ")
}
query.WriteString(c.toSelectField())
}
query.WriteString(" ")
query.WriteString("FROM ")
query.WriteString(b.q.table)
query.WriteString(" ")
err := b.wb.toWhereSQL(query, ¶ms)
if err != nil {
return "", nil, err
}
for i, order := range b.order {
if i == 0 {
query.WriteString(" ORDER BY ")
} else {
query.WriteString(", ")
}
query.WriteString(b.q.d.OrderExpression(order))
}
if b.limitDefined {
query.WriteString(" LIMIT ")
query.WriteString(strconv.FormatUint(b.limit, 10))
}
if b.offsetDefined {
query.WriteString(" OFFSET ")
query.WriteString(strconv.FormatUint(b.offset, 10))
}
return b.q.d.ReplacePlaceHolders(query.String()), params, nil
}
func (b *SelectBuilder) Rows(ctx context.Context, tx *Tx) (*Rows, error) {
return tx.query(ctx, b)
}
func (b *SelectBuilder) First(ctx context.Context, tx *Tx, dest interface{}) error {
rows, err := b.Rows(ctx, tx)
if err != nil {
return err
}
defer rows.Close()
if !rows.Next() {
if err := rows.Err(); err != nil {
return err
}
return ErrNotFound
}
return rows.Scan(dest)
}
func (b *SelectBuilder) All(ctx context.Context, tx *Tx, dest interface{}) error {
rows, err := b.Rows(ctx, tx)
if err != nil {
return err
}
defer rows.Close()
return rows.ScanAll(dest)
}