tidb functions 源码
tidb functions 代码
文件路径：/parser/ast/functions.go
// 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"
"time"
"github.com/pingcap/errors"
"github.com/pingcap/tidb/parser/format"
"github.com/pingcap/tidb/parser/model"
"github.com/pingcap/tidb/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"
RegexpLike = "regexp_like"
RegexpSubstr = "regexp_substr"
RegexpInStr = "regexp_instr"
RegexpReplace = "regexp_replace"
IsNull = "isnull"
IsTruthWithoutNull = "istrue" // Avoid name conflict with IsTrue in github/pingcap/check.
IsTruthWithNull = "istrue_with_null"
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 = "'tidb`.(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 = "'tidb`.(timeliteral"
TimeFormat = "time_format"
TimeToSec = "time_to_sec"
TimeDiff = "timediff"
Timestamp = "timestamp"
TimestampLiteral = "'tidb`.(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"
// TSO functions
// TiDBBoundedStaleness is used to determine the TS for a read only request with the given bounded staleness.
// It will be used in the Stale Read feature.
// For more info, please see AsOfClause.
TiDBBoundedStaleness = "tidb_bounded_staleness"
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"
OctetLength = "octet_length"
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"
Translate = "translate"
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"
WeightString = "weight_string"
Soundex = "soundex"
// 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"
TiDBDecodeBinaryPlan = "tidb_decode_binary_plan"
TiDBDecodeSQLDigests = "tidb_decode_sql_digests"
FormatBytes = "format_bytes"
FormatNanoTime = "format_nano_time"
// 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"
IsUUID = "is_uuid"
MasterPosWait = "master_pos_wait"
NameConst = "name_const"
ReleaseAllLocks = "release_all_locks"
Sleep = "sleep"
UUID = "uuid"
UUIDShort = "uuid_short"
UUIDToBin = "uuid_to_bin"
BinToUUID = "bin_to_uuid"
VitessHash = "vitess_hash"
TiDBShard = "tidb_shard"
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"
SM3 = "sm3"
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"
// TiDB internal function.
TiDBDecodeKey = "tidb_decode_key"
TiDBDecodeBase64Key = "tidb_decode_base64_key"
// MVCC information fetching function.
GetMvccInfo = "get_mvcc_info"
// Sequence function.
NextVal = "nextval"
LastVal = "lastval"
SetVal = "setval"
)
type FuncCallExprType int8
const (
FuncCallExprTypeKeyword FuncCallExprType = iota
FuncCallExprTypeGeneric
)
// FuncCallExpr is for function expression.
type FuncCallExpr struct {
funcNode
Tp FuncCallExprType
Schema model.CIStr
// FnName is the function name.
FnName model.CIStr
// Args is the function args.
Args []ExprNode
}
// Restore implements Node interface.
func (n *FuncCallExpr) Restore(ctx *format.RestoreCtx) error {
var specialLiteral string
switch n.FnName.L {
case DateLiteral:
specialLiteral = "DATE "
case TimeLiteral:
specialLiteral = "TIME "
case TimestampLiteral:
specialLiteral = "TIMESTAMP "
}
if specialLiteral != "" {
ctx.WritePlain(specialLiteral)
if err := n.Args[0].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCastExpr.Expr")
}
return nil
}
if len(n.Schema.String()) != 0 {
ctx.WriteName(n.Schema.O)
ctx.WritePlain(".")
}
if n.Tp == FuncCallExprTypeGeneric {
ctx.WriteName(n.FnName.O)
} else {
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 ")
if err := n.Args[1].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCastExpr.Expr")
}
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.Args[0]")
}
ctx.WritePlain(", ")
ctx.WriteKeyWord("INTERVAL ")
if err := n.Args[1].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr.Args[1]")
}
ctx.WritePlain(" ")
if err := n.Args[2].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr.Args[2]")
}
case "extract":
if err := n.Args[0].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr.Args[0]")
}
ctx.WriteKeyWord(" FROM ")
if err := n.Args[1].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr.Args[1]")
}
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 3:
if err := n.Args[2].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr.Args[2]")
}
ctx.WritePlain(" ")
fallthrough
case 2:
if expr, isValue := n.Args[1].(ValueExpr); !isValue || expr.GetValue() != nil {
if err := n.Args[1].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr.Args[1]")
}
ctx.WritePlain(" ")
}
ctx.WriteKeyWord("FROM ")
fallthrough
case 1:
if err := n.Args[0].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr.Args[0]")
}
}
case WeightString:
if err := n.Args[0].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr.(WEIGHT_STRING).Args[0]")
}
if len(n.Args) == 3 {
ctx.WriteKeyWord(" AS ")
ctx.WriteKeyWord(n.Args[1].(ValueExpr).GetValue().(string))
ctx.WritePlain("(")
if err := n.Args[2].Restore(ctx); err != nil {
return errors.Annotatef(err, "An error occurred while restore FuncCallExpr.(WEIGHT_STRING).Args[2]")
}
ctx.WritePlain(")")
}
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.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
// ExplicitCharSet is true when charset is explicit indicated.
ExplicitCharSet bool
}
// Restore implements Node interface.
func (n *FuncCastExpr) Restore(ctx *format.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, n.ExplicitCharSet)
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, n.ExplicitCharSet)
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, n.ExplicitCharSet)
fmt.Fprint(w, ")")
case CastConvertFunction:
fmt.Fprint(w, "CONVERT(")
n.Expr.Format(w)
fmt.Fprint(w, ", ")
n.Tp.FormatAsCastType(w, n.ExplicitCharSet)
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
)
// String implements fmt.Stringer interface.
func (direction TrimDirectionType) String() string {
switch direction {
case TrimBoth, TrimBothDefault:
return "BOTH"
case TrimLeading:
return "LEADING"
case TrimTrailing:
return "TRAILING"
default:
return ""
}
}
// TrimDirectionExpr is an expression representing the trim direction used in the TRIM() function.
type TrimDirectionExpr struct {
exprNode
// Direction is the trim direction
Direction TrimDirectionType
}
// Restore implements Node interface.
func (n *TrimDirectionExpr) Restore(ctx *format.RestoreCtx) error {
ctx.WriteKeyWord(n.Direction.String())
return nil
}
// Format the ExprNode into a Writer.
func (n *TrimDirectionExpr) Format(w io.Writer) {
fmt.Fprint(w, n.Direction.String())
}
// Accept implements Node Accept interface.
func (n *TrimDirectionExpr) Accept(v Visitor) (Node, bool) {
newNode, skipChildren := v.Enter(n)
if skipChildren {
return v.Leave(newNode)
}
return v.Leave(n)
}
// 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/std/stddev function
AggFuncStddevPop = "stddev_pop"
// AggFuncStddevSamp is the name of stddev_samp function
AggFuncStddevSamp = "stddev_samp"
// AggFuncJsonArrayagg is the name of json_arrayagg function
AggFuncJsonArrayagg = "json_arrayagg"
// AggFuncJsonObjectAgg is the name of json_objectagg function
AggFuncJsonObjectAgg = "json_objectagg"
// AggFuncApproxCountDistinct is the name of approx_count_distinct function.
AggFuncApproxCountDistinct = "approx_count_distinct"
// AggFuncApproxPercentile is the name of approx_percentile function.
AggFuncApproxPercentile = "approx_percentile"
)
// 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
// Order is only used in GROUP_CONCAT
Order *OrderByClause
}
// Restore implements Node interface.
func (n *AggregateFuncExpr) Restore(ctx *format.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)
}
}
if n.Order != nil {
ctx.WritePlain(" ")
if err := n.Order.Restore(ctx); err != nil {
return errors.Annotate(err, "An error occur while restore AggregateFuncExpr.Args Order")
}
}
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)
}
if n.Order != nil {
node, ok := n.Order.Accept(v)
if !ok {
return n, false
}
n.Order = node.(*OrderByClause)
}
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 *format.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)
}
// TimeUnitType is the type for time and timestamp units.
type TimeUnitType int
const (
// TimeUnitInvalid is a placeholder for an invalid time or timestamp unit
TimeUnitInvalid TimeUnitType = iota
// TimeUnitMicrosecond is the time or timestamp unit MICROSECOND.
TimeUnitMicrosecond
// TimeUnitSecond is the time or timestamp unit SECOND.
TimeUnitSecond
// TimeUnitMinute is the time or timestamp unit MINUTE.
TimeUnitMinute
// TimeUnitHour is the time or timestamp unit HOUR.
TimeUnitHour
// TimeUnitDay is the time or timestamp unit DAY.
TimeUnitDay
// TimeUnitWeek is the time or timestamp unit WEEK.
TimeUnitWeek
// TimeUnitMonth is the time or timestamp unit MONTH.
TimeUnitMonth
// TimeUnitQuarter is the time or timestamp unit QUARTER.
TimeUnitQuarter
// TimeUnitYear is the time or timestamp unit YEAR.
TimeUnitYear
// TimeUnitSecondMicrosecond is the time unit SECOND_MICROSECOND.
TimeUnitSecondMicrosecond
// TimeUnitMinuteMicrosecond is the time unit MINUTE_MICROSECOND.
TimeUnitMinuteMicrosecond
// TimeUnitMinuteSecond is the time unit MINUTE_SECOND.
TimeUnitMinuteSecond
// TimeUnitHourMicrosecond is the time unit HOUR_MICROSECOND.
TimeUnitHourMicrosecond
// TimeUnitHourSecond is the time unit HOUR_SECOND.
TimeUnitHourSecond
// TimeUnitHourMinute is the time unit HOUR_MINUTE.
TimeUnitHourMinute
// TimeUnitDayMicrosecond is the time unit DAY_MICROSECOND.
TimeUnitDayMicrosecond
// TimeUnitDaySecond is the time unit DAY_SECOND.
TimeUnitDaySecond
// TimeUnitDayMinute is the time unit DAY_MINUTE.
TimeUnitDayMinute
// TimeUnitDayHour is the time unit DAY_HOUR.
TimeUnitDayHour
// TimeUnitYearMonth is the time unit YEAR_MONTH.
TimeUnitYearMonth
)
// String implements fmt.Stringer interface.
func (unit TimeUnitType) String() string {
switch unit {
case TimeUnitMicrosecond:
return "MICROSECOND"
case TimeUnitSecond:
return "SECOND"
case TimeUnitMinute:
return "MINUTE"
case TimeUnitHour:
return "HOUR"
case TimeUnitDay:
return "DAY"
case TimeUnitWeek:
return "WEEK"
case TimeUnitMonth:
return "MONTH"
case TimeUnitQuarter:
return "QUARTER"
case TimeUnitYear:
return "YEAR"
case TimeUnitSecondMicrosecond:
return "SECOND_MICROSECOND"
case TimeUnitMinuteMicrosecond:
return "MINUTE_MICROSECOND"
case TimeUnitMinuteSecond:
return "MINUTE_SECOND"
case TimeUnitHourMicrosecond:
return "HOUR_MICROSECOND"
case TimeUnitHourSecond:
return "HOUR_SECOND"
case TimeUnitHourMinute:
return "HOUR_MINUTE"
case TimeUnitDayMicrosecond:
return "DAY_MICROSECOND"
case TimeUnitDaySecond:
return "DAY_SECOND"
case TimeUnitDayMinute:
return "DAY_MINUTE"
case TimeUnitDayHour:
return "DAY_HOUR"
case TimeUnitYearMonth:
return "YEAR_MONTH"
default:
return ""
}
}
// Duration represented by this unit.
// Returns error if the time unit is not a fixed time interval (such as MONTH)
// or a composite unit (such as MINUTE_SECOND).
func (unit TimeUnitType) Duration() (time.Duration, error) {
switch unit {
case TimeUnitMicrosecond:
return time.Microsecond, nil
case TimeUnitSecond:
return time.Second, nil
case TimeUnitMinute:
return time.Minute, nil
case TimeUnitHour:
return time.Hour, nil
case TimeUnitDay:
return time.Hour * 24, nil
case TimeUnitWeek:
return time.Hour * 24 * 7, nil
case TimeUnitMonth, TimeUnitQuarter, TimeUnitYear:
return 0, errors.Errorf("%s is not a constant time interval and cannot be used here", unit)
default:
return 0, errors.Errorf("%s is a composite time unit and is not supported yet", unit)
}
}
// TimeUnitExpr is an expression representing a time or timestamp unit.
type TimeUnitExpr struct {
exprNode
// Unit is the time or timestamp unit.
Unit TimeUnitType
}
// Restore implements Node interface.
func (n *TimeUnitExpr) Restore(ctx *format.RestoreCtx) error {
ctx.WriteKeyWord(n.Unit.String())
return nil
}
// Format the ExprNode into a Writer.
func (n *TimeUnitExpr) Format(w io.Writer) {
fmt.Fprint(w, n.Unit.String())
}
// Accept implements Node Accept interface.
func (n *TimeUnitExpr) Accept(v Visitor) (Node, bool) {
newNode, skipChildren := v.Enter(n)
if skipChildren {
return v.Leave(newNode)
}
return v.Leave(n)
}
// GetFormatSelectorType is the type for the first argument of GET_FORMAT() function.
type GetFormatSelectorType int
const (
// GetFormatSelectorDate is the GET_FORMAT selector DATE.
GetFormatSelectorDate GetFormatSelectorType = iota + 1
// GetFormatSelectorTime is the GET_FORMAT selector TIME.
GetFormatSelectorTime
// GetFormatSelectorDatetime is the GET_FORMAT selector DATETIME and TIMESTAMP.
GetFormatSelectorDatetime
)
// GetFormatSelectorExpr is an expression used as the first argument of GET_FORMAT() function.
type GetFormatSelectorExpr struct {
exprNode
// Selector is the GET_FORMAT() selector.
Selector GetFormatSelectorType
}
// String implements fmt.Stringer interface.
func (selector GetFormatSelectorType) String() string {
switch selector {
case GetFormatSelectorDate:
return "DATE"
case GetFormatSelectorTime:
return "TIME"
case GetFormatSelectorDatetime:
return "DATETIME"
default:
return ""
}
}
// Restore implements Node interface.
func (n *GetFormatSelectorExpr) Restore(ctx *format.RestoreCtx) error {
ctx.WriteKeyWord(n.Selector.String())
return nil
}
// Format the ExprNode into a Writer.
func (n *GetFormatSelectorExpr) Format(w io.Writer) {
fmt.Fprint(w, n.Selector.String())
}
// Accept implements Node Accept interface.
func (n *GetFormatSelectorExpr) Accept(v Visitor) (Node, bool) {
newNode, skipChildren := v.Enter(n)
if skipChildren {
return v.Leave(newNode)
}
return v.Leave(n)
}
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