forked from dolthub/go-mysql-server
/
rows.go
257 lines (222 loc) · 6.09 KB
/
rows.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
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
// Copyright 2020-2021 Dolthub, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package sql
import (
"fmt"
"io"
"strings"
"github.com/dolthub/vitess/go/vt/proto/query"
"github.com/gabereiser/go-mysql-server/sql/values"
)
// Row is a tuple of values.
type Row []interface{}
// NewRow creates a row from the given values.
func NewRow(values ...interface{}) Row {
row := make([]interface{}, len(values))
copy(row, values)
return row
}
// Copy creates a new row with the same values as the current one.
func (r Row) Copy() Row {
return NewRow(r...)
}
// Append appends all the values in r2 to this row and returns the result
func (r Row) Append(r2 Row) Row {
row := make(Row, len(r)+len(r2))
for i := range r {
row[i] = r[i]
}
for i := range r2 {
row[i+len(r)] = r2[i]
}
return row
}
// Equals checks whether two rows are equal given a schema.
func (r Row) Equals(row Row, schema Schema) (bool, error) {
if len(row) != len(r) || len(row) != len(schema) {
return false, nil
}
for i, colLeft := range r {
colRight := row[i]
cmp, err := schema[i].Type.Compare(colLeft, colRight)
if err != nil {
return false, err
}
if cmp != 0 {
return false, nil
}
}
return true, nil
}
// FormatRow returns a formatted string representing this row's values
func FormatRow(row Row) string {
var sb strings.Builder
sb.WriteRune('[')
for i, v := range row {
if i > 0 {
sb.WriteRune(',')
}
sb.WriteString(fmt.Sprintf("%v", v))
}
sb.WriteRune(']')
return sb.String()
}
// RowIter is an iterator that produces rows.
// TODO: most row iters need to be Disposable for CachedResult safety
type RowIter interface {
// Next retrieves the next row. It will return io.EOF if it's the last row.
// After retrieving the last row, Close will be automatically closed.
Next(ctx *Context) (Row, error)
Closer
}
// RowIter2 is an iterator that fills a row frame buffer with rows from its source
type RowIter2 interface {
RowIter
// Next2 produces the next row, and stores it in the RowFrame provided.
// It will return io.EOF if it's the last row. After retrieving the
// last row, Close will be automatically called.
Next2(ctx *Context, frame *RowFrame) error
}
// RowIterToRows converts a row iterator to a slice of rows.
func RowIterToRows(ctx *Context, sch Schema, i RowIter) ([]Row, error) {
if ri2, ok := i.(RowIterTypeSelector); ok && ri2.IsNode2() && sch != nil {
return RowIter2ToRows(ctx, sch, ri2.(RowIter2))
}
var rows []Row
for {
row, err := i.Next(ctx)
if err == io.EOF {
break
}
if err != nil {
i.Close(ctx)
return nil, err
}
rows = append(rows, row)
}
return rows, i.Close(ctx)
}
func RowIter2ToRows(ctx *Context, sch Schema, i RowIter2) ([]Row, error) {
var rows []Row
for {
f := NewRowFrame()
err := i.Next2(ctx, f)
if err == io.EOF {
break
}
if err != nil {
_ = i.Close(ctx)
return nil, err
}
rows = append(rows, rowFromRow2(sch, f.Row2()))
}
return rows, i.Close(ctx)
}
func rowFromRow2(sch Schema, r Row2) Row {
row := make(Row, len(sch))
for i, col := range sch {
switch col.Type.Type() {
case query.Type_INT8:
row[i] = values.ReadInt8(r.GetField(i).Val)
case query.Type_UINT8:
row[i] = values.ReadUint8(r.GetField(i).Val)
case query.Type_INT16:
row[i] = values.ReadInt16(r.GetField(i).Val)
case query.Type_UINT16:
row[i] = values.ReadUint16(r.GetField(i).Val)
case query.Type_INT32:
row[i] = values.ReadInt32(r.GetField(i).Val)
case query.Type_UINT32:
row[i] = values.ReadUint32(r.GetField(i).Val)
case query.Type_INT64:
row[i] = values.ReadInt64(r.GetField(i).Val)
case query.Type_UINT64:
row[i] = values.ReadUint64(r.GetField(i).Val)
case query.Type_FLOAT32:
row[i] = values.ReadFloat32(r.GetField(i).Val)
case query.Type_FLOAT64:
row[i] = values.ReadFloat64(r.GetField(i).Val)
case query.Type_TEXT, query.Type_VARCHAR, query.Type_CHAR:
row[i] = values.ReadString(r.GetField(i).Val, values.ByteOrderCollation)
case query.Type_BLOB, query.Type_VARBINARY, query.Type_BINARY:
row[i] = values.ReadBytes(r.GetField(i).Val, values.ByteOrderCollation)
case query.Type_BIT:
fallthrough
case query.Type_ENUM:
fallthrough
case query.Type_SET:
fallthrough
case query.Type_TUPLE:
fallthrough
case query.Type_GEOMETRY:
fallthrough
case query.Type_JSON:
fallthrough
case query.Type_EXPRESSION:
fallthrough
case query.Type_INT24:
fallthrough
case query.Type_UINT24:
fallthrough
case query.Type_TIMESTAMP:
fallthrough
case query.Type_DATE:
fallthrough
case query.Type_TIME:
fallthrough
case query.Type_DATETIME:
fallthrough
case query.Type_YEAR:
fallthrough
case query.Type_DECIMAL:
panic(fmt.Sprintf("Unimplemented type conversion: %T", col.Type))
default:
panic(fmt.Sprintf("unknown type %T", col.Type))
}
}
return row
}
// NodeToRows converts a node to a slice of rows.
func NodeToRows(ctx *Context, n Node) ([]Row, error) {
i, err := n.RowIter(ctx, nil)
if err != nil {
return nil, err
}
return RowIterToRows(ctx, nil, i)
}
// RowsToRowIter creates a RowIter that iterates over the given rows.
func RowsToRowIter(rows ...Row) RowIter {
return &sliceRowIter{rows: rows}
}
type sliceRowIter struct {
rows []Row
idx int
}
func (i *sliceRowIter) Next(*Context) (Row, error) {
if i.idx >= len(i.rows) {
return nil, io.EOF
}
r := i.rows[i.idx]
i.idx++
return r.Copy(), nil
}
func (i *sliceRowIter) Close(*Context) error {
i.rows = nil
return nil
}
// RowIterTypeSelector is implemented by top-level type-switch nodes that return either a Node or Node2 implementation.
type RowIterTypeSelector interface {
RowIter
IsNode2() bool
}