forked from pingcap/parser
-
Notifications
You must be signed in to change notification settings - Fork 0
/
functions.go
executable file
·801 lines (760 loc) · 22.6 KB
/
functions.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
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
// Copyright 2015 PingCAP, 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,
// See the License for the specific language governing permissions and
// limitations under the License.
package ast
import (
"fmt"
"io"
"strings"
"github.com/pingcap/errors"
. "github.com/pingcap/parser/format"
"github.com/pingcap/parser/model"
"github.com/pingcap/parser/types"
)
var (
_ FuncNode = &AggregateFuncExpr{}
_ FuncNode = &FuncCallExpr{}
_ FuncNode = &FuncCastExpr{}
_ FuncNode = &WindowFuncExpr{}
)
// List scalar function names.
const (
LogicAnd = "and"
Cast = "cast"
LeftShift = "leftshift"
RightShift = "rightshift"
LogicOr = "or"
GE = "ge"
LE = "le"
EQ = "eq"
NE = "ne"
LT = "lt"
GT = "gt"
Plus = "plus"
Minus = "minus"
And = "bitand"
Or = "bitor"
Mod = "mod"
Xor = "bitxor"
Div = "div"
Mul = "mul"
UnaryNot = "not" // Avoid name conflict with Not in github/pingcap/check.
BitNeg = "bitneg"
IntDiv = "intdiv"
LogicXor = "xor"
NullEQ = "nulleq"
UnaryPlus = "unaryplus"
UnaryMinus = "unaryminus"
In = "in"
Like = "like"
Case = "case"
Regexp = "regexp"
IsNull = "isnull"
IsTruth = "istrue" // Avoid name conflict with IsTrue in github/pingcap/check.
IsFalsity = "isfalse" // Avoid name conflict with IsFalse in github/pingcap/check.
RowFunc = "row"
SetVar = "setvar"
GetVar = "getvar"
Values = "values"
BitCount = "bit_count"
GetParam = "getparam"
// common functions
Coalesce = "coalesce"
Greatest = "greatest"
Least = "least"
Interval = "interval"
// math functions
Abs = "abs"
Acos = "acos"
Asin = "asin"
Atan = "atan"
Atan2 = "atan2"
Ceil = "ceil"
Ceiling = "ceiling"
Conv = "conv"
Cos = "cos"
Cot = "cot"
CRC32 = "crc32"
Degrees = "degrees"
Exp = "exp"
Floor = "floor"
Ln = "ln"
Log = "log"
Log2 = "log2"
Log10 = "log10"
PI = "pi"
Pow = "pow"
Power = "power"
Radians = "radians"
Rand = "rand"
Round = "round"
Sign = "sign"
Sin = "sin"
Sqrt = "sqrt"
Tan = "tan"
Truncate = "truncate"
// time functions
AddDate = "adddate"
AddTime = "addtime"
ConvertTz = "convert_tz"
Curdate = "curdate"
CurrentDate = "current_date"
CurrentTime = "current_time"
CurrentTimestamp = "current_timestamp"
Curtime = "curtime"
Date = "date"
DateLiteral = "dateliteral"
DateAdd = "date_add"
DateFormat = "date_format"
DateSub = "date_sub"
DateDiff = "datediff"
Day = "day"
DayName = "dayname"
DayOfMonth = "dayofmonth"
DayOfWeek = "dayofweek"
DayOfYear = "dayofyear"
Extract = "extract"
FromDays = "from_days"
FromUnixTime = "from_unixtime"
GetFormat = "get_format"
Hour = "hour"
LocalTime = "localtime"
LocalTimestamp = "localtimestamp"
MakeDate = "makedate"
MakeTime = "maketime"
MicroSecond = "microsecond"
Minute = "minute"
Month = "month"
MonthName = "monthname"
Now = "now"
PeriodAdd = "period_add"
PeriodDiff = "period_diff"
Quarter = "quarter"
SecToTime = "sec_to_time"
Second = "second"
StrToDate = "str_to_date"
SubDate = "subdate"
SubTime = "subtime"
Sysdate = "sysdate"
Time = "time"
TimeLiteral = "timeliteral"
TimeFormat = "time_format"
TimeToSec = "time_to_sec"
TimeDiff = "timediff"
Timestamp = "timestamp"
TimestampLiteral = "timestampliteral"
TimestampAdd = "timestampadd"
TimestampDiff = "timestampdiff"
ToDays = "to_days"
ToSeconds = "to_seconds"
UnixTimestamp = "unix_timestamp"
UTCDate = "utc_date"
UTCTime = "utc_time"
UTCTimestamp = "utc_timestamp"
Week = "week"
Weekday = "weekday"
WeekOfYear = "weekofyear"
Year = "year"
YearWeek = "yearweek"
LastDay = "last_day"
TiDBParseTso = "tidb_parse_tso"
// string functions
ASCII = "ascii"
Bin = "bin"
Concat = "concat"
ConcatWS = "concat_ws"
Convert = "convert"
Elt = "elt"
ExportSet = "export_set"
Field = "field"
Format = "format"
FromBase64 = "from_base64"
InsertFunc = "insert_func"
Instr = "instr"
Lcase = "lcase"
Left = "left"
Length = "length"
LoadFile = "load_file"
Locate = "locate"
Lower = "lower"
Lpad = "lpad"
LTrim = "ltrim"
MakeSet = "make_set"
Mid = "mid"
Oct = "oct"
Ord = "ord"
Position = "position"
Quote = "quote"
Repeat = "repeat"
Replace = "replace"
Reverse = "reverse"
Right = "right"
RTrim = "rtrim"
Space = "space"
Strcmp = "strcmp"
Substring = "substring"
Substr = "substr"
SubstringIndex = "substring_index"
ToBase64 = "to_base64"
Trim = "trim"
Upper = "upper"
Ucase = "ucase"
Hex = "hex"
Unhex = "unhex"
Rpad = "rpad"
BitLength = "bit_length"
CharFunc = "char_func"
CharLength = "char_length"
CharacterLength = "character_length"
FindInSet = "find_in_set"
// information functions
Benchmark = "benchmark"
Charset = "charset"
Coercibility = "coercibility"
Collation = "collation"
ConnectionID = "connection_id"
CurrentUser = "current_user"
CurrentRole = "current_role"
Database = "database"
FoundRows = "found_rows"
LastInsertId = "last_insert_id"
RowCount = "row_count"
Schema = "schema"
SessionUser = "session_user"
SystemUser = "system_user"
User = "user"
Version = "version"
TiDBVersion = "tidb_version"
TiDBIsDDLOwner = "tidb_is_ddl_owner"
TiDBDecodePlan = "tidb_decode_plan"
// control functions
If = "if"
Ifnull = "ifnull"
Nullif = "nullif"
// miscellaneous functions
AnyValue = "any_value"
DefaultFunc = "default_func"
InetAton = "inet_aton"
InetNtoa = "inet_ntoa"
Inet6Aton = "inet6_aton"
Inet6Ntoa = "inet6_ntoa"
IsFreeLock = "is_free_lock"
IsIPv4 = "is_ipv4"
IsIPv4Compat = "is_ipv4_compat"
IsIPv4Mapped = "is_ipv4_mapped"
IsIPv6 = "is_ipv6"
IsUsedLock = "is_used_lock"
MasterPosWait = "master_pos_wait"
NameConst = "name_const"
ReleaseAllLocks = "release_all_locks"
Sleep = "sleep"
UUID = "uuid"
UUIDShort = "uuid_short"
// get_lock() and release_lock() is parsed but do nothing.
// It is used for preventing error in Ruby's activerecord migrations.
GetLock = "get_lock"
ReleaseLock = "release_lock"
// encryption and compression functions
AesDecrypt = "aes_decrypt"
AesEncrypt = "aes_encrypt"
Compress = "compress"
Decode = "decode"
DesDecrypt = "des_decrypt"
DesEncrypt = "des_encrypt"
Encode = "encode"
Encrypt = "encrypt"
MD5 = "md5"
OldPassword = "old_password"
PasswordFunc = "password_func"
RandomBytes = "random_bytes"
SHA1 = "sha1"
SHA = "sha"
SHA2 = "sha2"
Uncompress = "uncompress"
UncompressedLength = "uncompressed_length"
ValidatePasswordStrength = "validate_password_strength"
// json functions
JSONType = "json_type"
JSONExtract = "json_extract"
JSONUnquote = "json_unquote"
JSONArray = "json_array"
JSONObject = "json_object"
JSONMerge = "json_merge"
JSONSet = "json_set"
JSONInsert = "json_insert"
JSONReplace = "json_replace"
JSONRemove = "json_remove"
JSONContains = "json_contains"
JSONContainsPath = "json_contains_path"
JSONValid = "json_valid"
JSONArrayAppend = "json_array_append"
JSONArrayInsert = "json_array_insert"
JSONMergePatch = "json_merge_patch"
JSONMergePreserve = "json_merge_preserve"
JSONPretty = "json_pretty"
JSONQuote = "json_quote"
JSONSearch = "json_search"
JSONStorageSize = "json_storage_size"
JSONDepth = "json_depth"
JSONKeys = "json_keys"
JSONLength = "json_length"
)
// FuncCallExpr is for function expression.
type FuncCallExpr struct {
funcNode
// FnName is the function name.
FnName model.CIStr
// Args is the function args.
Args []ExprNode
}
// Restore implements Node interface.
func (n *FuncCallExpr) Restore(ctx *RestoreCtx) error {
ctx.WriteKeyWord(n.FnName.O)
ctx.WritePlain("(")
switch n.FnName.L {
case "convert":
if err := n.Args[0].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCastExpr.Expr")
}
ctx.WriteKeyWord(" USING ")
ctx.WriteKeyWord(n.Args[1].GetType().Charset)
case "adddate", "subdate", "date_add", "date_sub":
if err := n.Args[0].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr")
}
ctx.WritePlain(", ")
ctx.WriteKeyWord("INTERVAL ")
if err := n.Args[1].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr")
}
ctx.WritePlain(" ")
ctx.WriteKeyWord(n.Args[2].(ValueExpr).GetString())
case "extract":
ctx.WriteKeyWord(n.Args[0].(ValueExpr).GetString())
ctx.WriteKeyWord(" FROM ")
if err := n.Args[1].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr")
}
case "get_format":
ctx.WriteKeyWord(n.Args[0].(ValueExpr).GetString())
ctx.WritePlain(", ")
if err := n.Args[1].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr")
}
case "position":
if err := n.Args[0].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr")
}
ctx.WriteKeyWord(" IN ")
if err := n.Args[1].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr")
}
case "trim":
switch len(n.Args) {
case 1:
if err := n.Args[0].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr")
}
case 2:
if err := n.Args[1].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr")
}
ctx.WriteKeyWord(" FROM ")
if err := n.Args[0].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr")
}
case 3:
switch fmt.Sprint(n.Args[2].(ValueExpr).GetValue()) {
case "3":
ctx.WriteKeyWord("TRAILING ")
case "2":
ctx.WriteKeyWord("LEADING ")
case "0", "1":
ctx.WriteKeyWord("BOTH ")
}
if n.Args[1].(ValueExpr).GetValue() != nil {
if err := n.Args[1].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr")
}
ctx.WritePlain(" ")
}
ctx.WriteKeyWord("FROM ")
if err := n.Args[0].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr")
}
}
case "timestampdiff", "timestampadd":
ctx.WriteKeyWord(n.Args[0].(ValueExpr).GetString())
for i := 1; i < len(n.Args); {
ctx.WritePlain(", ")
if err := n.Args[i].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr")
}
i++
}
default:
for i, argv := range n.Args {
if i != 0 {
ctx.WritePlain(", ")
}
if err := argv.Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr.Args %d", i)
}
}
}
ctx.WritePlain(")")
return nil
}
// Format the ExprNode into a Writer.
func (n *FuncCallExpr) Format(w io.Writer) {
fmt.Fprintf(w, "%s(", n.FnName.L)
if !n.specialFormatArgs(w) {
for i, arg := range n.Args {
arg.Format(w)
if i != len(n.Args)-1 {
fmt.Fprint(w, ", ")
}
}
}
fmt.Fprint(w, ")")
}
// specialFormatArgs formats argument list for some special functions.
func (n *FuncCallExpr) specialFormatArgs(w io.Writer) bool {
switch n.FnName.L {
case DateAdd, DateSub, AddDate, SubDate:
n.Args[0].Format(w)
fmt.Fprint(w, ", INTERVAL ")
n.Args[1].Format(w)
fmt.Fprintf(w, " %s", n.Args[2].(ValueExpr).GetDatumString())
return true
case TimestampAdd, TimestampDiff:
fmt.Fprintf(w, "%s, ", n.Args[0].(ValueExpr).GetDatumString())
n.Args[1].Format(w)
fmt.Fprint(w, ", ")
n.Args[2].Format(w)
return true
}
return false
}
// Accept implements Node interface.
func (n *FuncCallExpr) Accept(v Visitor) (Node, bool) {
newNode, skipChildren := v.Enter(n)
if skipChildren {
return v.Leave(newNode)
}
n = newNode.(*FuncCallExpr)
for i, val := range n.Args {
node, ok := val.Accept(v)
if !ok {
return n, false
}
n.Args[i] = node.(ExprNode)
}
return v.Leave(n)
}
// CastFunctionType is the type for cast function.
type CastFunctionType int
// CastFunction types
const (
CastFunction CastFunctionType = iota + 1
CastConvertFunction
CastBinaryOperator
)
// FuncCastExpr is the cast function converting value to another type, e.g, cast(expr AS signed).
// See https://dev.mysql.com/doc/refman/5.7/en/cast-functions.html
type FuncCastExpr struct {
funcNode
// Expr is the expression to be converted.
Expr ExprNode
// Tp is the conversion type.
Tp *types.FieldType
// FunctionType is either Cast, Convert or Binary.
FunctionType CastFunctionType
}
// Restore implements Node interface.
func (n *FuncCastExpr) Restore(ctx *RestoreCtx) error {
switch n.FunctionType {
case CastFunction:
ctx.WriteKeyWord("CAST")
ctx.WritePlain("(")
if err := n.Expr.Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCastExpr.Expr")
}
ctx.WriteKeyWord(" AS ")
n.Tp.RestoreAsCastType(ctx)
ctx.WritePlain(")")
case CastConvertFunction:
ctx.WriteKeyWord("CONVERT")
ctx.WritePlain("(")
if err := n.Expr.Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCastExpr.Expr")
}
ctx.WritePlain(", ")
n.Tp.RestoreAsCastType(ctx)
ctx.WritePlain(")")
case CastBinaryOperator:
ctx.WriteKeyWord("BINARY ")
if err := n.Expr.Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCastExpr.Expr")
}
}
return nil
}
// Format the ExprNode into a Writer.
func (n *FuncCastExpr) Format(w io.Writer) {
switch n.FunctionType {
case CastFunction:
fmt.Fprint(w, "CAST(")
n.Expr.Format(w)
fmt.Fprint(w, " AS ")
n.Tp.FormatAsCastType(w)
fmt.Fprint(w, ")")
case CastConvertFunction:
fmt.Fprint(w, "CONVERT(")
n.Expr.Format(w)
fmt.Fprint(w, ", ")
n.Tp.FormatAsCastType(w)
fmt.Fprint(w, ")")
case CastBinaryOperator:
fmt.Fprint(w, "BINARY ")
n.Expr.Format(w)
}
}
// Accept implements Node Accept interface.
func (n *FuncCastExpr) Accept(v Visitor) (Node, bool) {
newNode, skipChildren := v.Enter(n)
if skipChildren {
return v.Leave(newNode)
}
n = newNode.(*FuncCastExpr)
node, ok := n.Expr.Accept(v)
if !ok {
return n, false
}
n.Expr = node.(ExprNode)
return v.Leave(n)
}
// TrimDirectionType is the type for trim direction.
type TrimDirectionType int
const (
// TrimBothDefault trims from both direction by default.
TrimBothDefault TrimDirectionType = iota
// TrimBoth trims from both direction with explicit notation.
TrimBoth
// TrimLeading trims from left.
TrimLeading
// TrimTrailing trims from right.
TrimTrailing
)
// DateArithType is type for DateArith type.
type DateArithType byte
const (
// DateArithAdd is to run adddate or date_add function option.
// See https://dev.mysql.com/doc/refman/5.7/en/date-and-time-functions.html#function_adddate
// See https://dev.mysql.com/doc/refman/5.7/en/date-and-time-functions.html#function_date-add
DateArithAdd DateArithType = iota + 1
// DateArithSub is to run subdate or date_sub function option.
// See https://dev.mysql.com/doc/refman/5.7/en/date-and-time-functions.html#function_subdate
// See https://dev.mysql.com/doc/refman/5.7/en/date-and-time-functions.html#function_date-sub
DateArithSub
)
const (
// AggFuncCount is the name of Count function.
AggFuncCount = "count"
// AggFuncSum is the name of Sum function.
AggFuncSum = "sum"
// AggFuncAvg is the name of Avg function.
AggFuncAvg = "avg"
// AggFuncFirstRow is the name of FirstRowColumn function.
AggFuncFirstRow = "firstrow"
// AggFuncMax is the name of max function.
AggFuncMax = "max"
// AggFuncMin is the name of min function.
AggFuncMin = "min"
// AggFuncGroupConcat is the name of group_concat function.
AggFuncGroupConcat = "group_concat"
// AggFuncBitOr is the name of bit_or function.
AggFuncBitOr = "bit_or"
// AggFuncBitXor is the name of bit_xor function.
AggFuncBitXor = "bit_xor"
// AggFuncBitAnd is the name of bit_and function.
AggFuncBitAnd = "bit_and"
// AggFuncVarPop is the name of var_pop function
AggFuncVarPop = "var_pop"
// AggFuncVarSamp is the name of var_samp function
AggFuncVarSamp = "var_samp"
// AggFuncStddevPop is the name of stddev_pop function
AggFuncStddevPop = "stddev_pop"
// AggFuncStddevSamp is the name of stddev_samp function
AggFuncStddevSamp = "stddev_samp"
)
// AggregateFuncExpr represents aggregate function expression.
type AggregateFuncExpr struct {
funcNode
// F is the function name.
F string
// Args is the function args.
Args []ExprNode
// Distinct is true, function hence only aggregate distinct values.
// For example, column c1 values are "1", "2", "2", "sum(c1)" is "5",
// but "sum(distinct c1)" is "3".
Distinct bool
}
// Restore implements Node interface.
func (n *AggregateFuncExpr) Restore(ctx *RestoreCtx) error {
ctx.WriteKeyWord(n.F)
ctx.WritePlain("(")
if n.Distinct {
ctx.WriteKeyWord("DISTINCT ")
}
switch strings.ToLower(n.F) {
case "group_concat":
for i := 0; i < len(n.Args)-1; i++ {
if i != 0 {
ctx.WritePlain(", ")
}
if err := n.Args[i].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore AggregateFuncExpr.Args[%d]", i)
}
}
ctx.WriteKeyWord(" SEPARATOR ")
if err := n.Args[len(n.Args)-1].Restore(ctx); err != nil {
return errors.Annotate(err, "An error occurred while restore AggregateFuncExpr.Args SEPARATOR")
}
default:
for i, argv := range n.Args {
if i != 0 {
ctx.WritePlain(", ")
}
if err := argv.Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore AggregateFuncExpr.Args[%d]", i)
}
}
}
ctx.WritePlain(")")
return nil
}
// Format the ExprNode into a Writer.
func (n *AggregateFuncExpr) Format(w io.Writer) {
panic("Not implemented")
}
// Accept implements Node Accept interface.
func (n *AggregateFuncExpr) Accept(v Visitor) (Node, bool) {
newNode, skipChildren := v.Enter(n)
if skipChildren {
return v.Leave(newNode)
}
n = newNode.(*AggregateFuncExpr)
for i, val := range n.Args {
node, ok := val.Accept(v)
if !ok {
return n, false
}
n.Args[i] = node.(ExprNode)
}
return v.Leave(n)
}
const (
// WindowFuncRowNumber is the name of row_number function.
WindowFuncRowNumber = "row_number"
// WindowFuncRank is the name of rank function.
WindowFuncRank = "rank"
// WindowFuncDenseRank is the name of dense_rank function.
WindowFuncDenseRank = "dense_rank"
// WindowFuncCumeDist is the name of cume_dist function.
WindowFuncCumeDist = "cume_dist"
// WindowFuncPercentRank is the name of percent_rank function.
WindowFuncPercentRank = "percent_rank"
// WindowFuncNtile is the name of ntile function.
WindowFuncNtile = "ntile"
// WindowFuncLead is the name of lead function.
WindowFuncLead = "lead"
// WindowFuncLag is the name of lag function.
WindowFuncLag = "lag"
// WindowFuncFirstValue is the name of first_value function.
WindowFuncFirstValue = "first_value"
// WindowFuncLastValue is the name of last_value function.
WindowFuncLastValue = "last_value"
// WindowFuncNthValue is the name of nth_value function.
WindowFuncNthValue = "nth_value"
)
// WindowFuncExpr represents window function expression.
type WindowFuncExpr struct {
funcNode
// F is the function name.
F string
// Args is the function args.
Args []ExprNode
// Distinct cannot be true for most window functions, except `max` and `min`.
// We need to raise error if it is not allowed to be true.
Distinct bool
// IgnoreNull indicates how to handle null value.
// MySQL only supports `RESPECT NULLS`, so we need to raise error if it is true.
IgnoreNull bool
// FromLast indicates the calculation direction of this window function.
// MySQL only supports calculation from first, so we need to raise error if it is true.
FromLast bool
// Spec is the specification of this window.
Spec WindowSpec
}
// Restore implements Node interface.
func (n *WindowFuncExpr) Restore(ctx *RestoreCtx) error {
ctx.WriteKeyWord(n.F)
ctx.WritePlain("(")
for i, v := range n.Args {
if i != 0 {
ctx.WritePlain(", ")
} else if n.Distinct {
ctx.WriteKeyWord("DISTINCT ")
}
if err := v.Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore WindowFuncExpr.Args[%d]", i)
}
}
ctx.WritePlain(")")
if n.FromLast {
ctx.WriteKeyWord(" FROM LAST")
}
if n.IgnoreNull {
ctx.WriteKeyWord(" IGNORE NULLS")
}
ctx.WriteKeyWord(" OVER ")
if err := n.Spec.Restore(ctx); err != nil {
return errors.Annotate(err, "An error occurred while restore WindowFuncExpr.Spec")
}
return nil
}
// Format formats the window function expression into a Writer.
func (n *WindowFuncExpr) Format(w io.Writer) {
panic("Not implemented")
}
// Accept implements Node Accept interface.
func (n *WindowFuncExpr) Accept(v Visitor) (Node, bool) {
newNode, skipChildren := v.Enter(n)
if skipChildren {
return v.Leave(newNode)
}
n = newNode.(*WindowFuncExpr)
for i, val := range n.Args {
node, ok := val.Accept(v)
if !ok {
return n, false
}
n.Args[i] = node.(ExprNode)
}
node, ok := n.Spec.Accept(v)
if !ok {
return n, false
}
n.Spec = *node.(*WindowSpec)
return v.Leave(n)
}