types

package
v0.0.0-...-815d2fd Latest Latest
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 Go to latest Published: Jul 15, 2016 License: Apache-2.0 Imports: 14 Imported by: 0

Documentation

Index

Constants

View Source 
const (
	KindNull  byte = 0
	KindInt64 byte = iota + 1
	KindUint64
	KindFloat32
	KindFloat64
	KindString
	KindBytes
	KindMysqlBit
	KindMysqlDecimal
	KindMysqlDuration
	KindMysqlEnum
	KindMysqlHex
	KindMysqlSet
	KindMysqlTime
	KindRow
	KindInterface
	KindMinNotNull
	KindMaxValue
)

Kind constants.

View Source 
const (
	UnspecifiedLength int = -1
)

UnspecifiedLength is unspecified length.

Variables

View Source 
var ErrArithOverflow = errors.New("operation overflow")

ErrArithOverflow is the error for arthimetic operation overflow.

View Source 
var (
	// ErrValueTruncated is used when a value has been truncated during conversion.
	ErrValueTruncated = errors.New("value has been truncated")
)

Functions

func AddInt64 

func AddInt64(a int64, b int64) (int64, error)

AddInt64 adds int64 a and b if no overflow, otherwise returns error.

func AddInteger 

func AddInteger(a uint64, b int64) (uint64, error)

AddInteger adds uint64 a and int64 b and returns uint64 if no overflow error.

func AddUint64 

func AddUint64(a uint64, b uint64) (uint64, error)

AddUint64 adds uint64 a and b if no overflow, else returns error.

func CalculateSum 

func CalculateSum(sum interface{}, v interface{}) (interface{}, error)

CalculateSum adds v to sum.

func Compare 

func Compare(a, b interface{}) (int, error)

Compare returns an integer comparing the interface a with b. a > b -> 1 a = b -> 0 a < b -> -1

func CompareFloat64 

func CompareFloat64(x, y float64) int

CompareFloat64 returns an integer comparing the float64 x to y.

func CompareInt64 

func CompareInt64(x, y int64) int

CompareInt64 returns an integer comparing the int64 x to y.

func CompareString 

func CompareString(x, y string) int

CompareString returns an integer comparing the string x to y.

func CompareUint64 

func CompareUint64(x, y uint64) int

CompareUint64 returns an integer comparing the uint64 x to y.

func Convert 

func Convert(val interface{}, target *FieldType) (v interface{}, err error)

Convert converts the val with type tp.

func ConvertDatumToDecimal 

func ConvertDatumToDecimal(d Datum) (mysql.Decimal, error)

ConvertDatumToDecimal converts datum to decimal.

func DatumsToInterfaces 

func DatumsToInterfaces(datums []Datum) []interface{}

DatumsToInterfaces converts a datum slice to interface slice.

func DefaultCharsetForType 

func DefaultCharsetForType(tp byte) (string, string)

DefaultCharsetForType returns the default charset/collation for mysql type.

func DivInt64 

func DivInt64(a int64, b int64) (int64, error)

DivInt64 divides int64 a with b, returns int64 if no overflow error. It just checks overflow, if b is zero, a "divide by zero" panic throws.

func DivIntWithUint 

func DivIntWithUint(a int64, b uint64) (uint64, error)

DivIntWithUint divides int64 a with uint64 b, returns uint64 if no overflow error. It just checks overflow, if b is zero, a "divide by zero" panic throws.

func DivUintWithInt 

func DivUintWithInt(a uint64, b int64) (uint64, error)

DivUintWithInt divides uint64 a with int64 b, returns uint64 if no overflow error. It just checks overflow, if b is zero, a "divide by zero" panic throws.

func EOFAsNil 

func EOFAsNil(err error) error

EOFAsNil filtrates errors, If err is equal to io.EOF returns nil.

func EqualDatums 

func EqualDatums(a []Datum, b []Datum) (bool, error)

EqualDatums compare if a and b contains the same datum values.

func InvOp2 

func InvOp2(x, y interface{}, o opcode.Op) (interface{}, error)

InvOp2 returns an invalid operation error.

func IsTypeBlob 

func IsTypeBlob(tp byte) bool

IsTypeBlob returns a boolean indicating whether the tp is a blob type.

func IsTypeChar 

func IsTypeChar(tp byte) bool

IsTypeChar returns a boolean indicating whether the tp is the char type like a string type or a varchar type.

func MergeFieldType 

func MergeFieldType(a byte, b byte) byte

MergeFieldType merges two MySQL type to a new type. This is used in hybrid field type expression. For example "select case c when 1 then 2 when 2 then 'tidb' from t;" The resule field type of the case expression is the merged type of the two when clause. See https://github.com/mysql/mysql-server/blob/5.7/sql/field.cc#L1042

func MulInt64 

func MulInt64(a int64, b int64) (int64, error)

MulInt64 multiplies int64 a and b and returns int64 if no overflow error.

func MulInteger 

func MulInteger(a uint64, b int64) (uint64, error)

MulInteger multiplies uint64 a and int64 b, and returns uint64 if no overflow error.

func MulUint64 

func MulUint64(a uint64, b uint64) (uint64, error)

MulUint64 multiplies uint64 a and b and returns uint64 if no overflow error.

func Round 

func Round(f float64, dec int) float64

Round rounds the argument f to dec decimal places. dec defaults to 0 if not specified. dec can be negative to cause dec digits left of the decimal point of the value f to become zero.

func RoundFloat 

func RoundFloat(f float64) float64

RoundFloat rounds float val to the nearest integer value with float64 format, like MySQL Round function. RoundFloat uses default rounding mode, see https://dev.mysql.com/doc/refman/5.7/en/precision-math-rounding.html so rounding use "round half away from zero". e.g, 1.5 -> 2, -1.5 -> -2.

func SortDatums 

func SortDatums(datums []Datum) error

SortDatums sorts a slice of datum.

func StrToFloat 

func StrToFloat(str string) (float64, error)

StrToFloat converts a string to a float64 in best effort.

func StrToInt 

func StrToInt(str string) (int64, error)

StrToInt converts a string to an integer in best effort. TODO: handle overflow and add unittest.

func SubInt64 

func SubInt64(a int64, b int64) (int64, error)

SubInt64 subtracts int64 a with b and returns int64 if no overflow error.

func SubIntWithUint 

func SubIntWithUint(a int64, b uint64) (uint64, error)

SubIntWithUint subtracts int64 a with uint64 b and returns uint64 if no overflow error.

func SubUint64 

func SubUint64(a uint64, b uint64) (uint64, error)

SubUint64 subtracts uint64 a with b and returns uint64 if no overflow error.

func SubUintWithInt 

func SubUintWithInt(a uint64, b int64) (uint64, error)

SubUintWithInt subtracts uint64 a with int64 b and returns uint64 if no overflow error.

func ToString 

func ToString(value interface{}) (string, error)

ToString converts an interface to a string.

func TruncateFloat 

func TruncateFloat(f float64, flen int, decimal int) (float64, error)

TruncateFloat tries to truncate f. If the result exceeds the max/min float that flen/decimal allowed, returns the max/min float allowed.

func TypeStr 

func TypeStr(tp byte) (r string)

TypeStr converts tp to a string.

func TypeToStr 

func TypeToStr(tp byte, cs string) (r string)

TypeToStr converts a field to a string. It is used for converting Text to Blob, or converting Char to Binary. Args: 

tp: type enum
cs: charset

Types

type Datum 

type Datum struct {
	// contains filtered or unexported fields
}

Datum is a data box holds different kind of data. It has better performance and is easier to use than `interface{}`.

func CoerceArithmetic 

func CoerceArithmetic(a Datum) (d Datum, err error)

CoerceArithmetic converts datum to appropriate datum for arithmetic computing.

func CoerceDatum 

func CoerceDatum(a, b Datum) (x, y Datum)

CoerceDatum changes type. If a or b is Decimal, changes the both to Decimal. Else if a or b is Float, changes the both to Float.

func ComputeDiv 

func ComputeDiv(a, b Datum) (d Datum, err error)

ComputeDiv computes the result of a/b.

func ComputeIntDiv 

func ComputeIntDiv(a, b Datum) (d Datum, err error)

ComputeIntDiv computes the result of a / b, both a and b are integer.

func ComputeMinus 

func ComputeMinus(a, b Datum) (d Datum, err error)

ComputeMinus computes the result of a-b.

func ComputeMod 

func ComputeMod(a, b Datum) (d Datum, err error)

ComputeMod computes the result of a mod b.

func ComputeMul 

func ComputeMul(a, b Datum) (d Datum, err error)

ComputeMul computes the result of a*b.

func ComputePlus 

func ComputePlus(a, b Datum) (d Datum, err error)

ComputePlus computes the result of a+b.

func MakeDatums 

func MakeDatums(args ...interface{}) []Datum

MakeDatums creates datum slice from interfaces.

func MaxValueDatum 

func MaxValueDatum() Datum

MaxValueDatum returns a datum represents max value.

func MinNotNullDatum 

func MinNotNullDatum() Datum

MinNotNullDatum returns a datum represents minimum not null value.

func NewBytesDatum 

func NewBytesDatum(b []byte) (d Datum)

NewBytesDatum creates a new Datum from a byte slice.

func NewDatum 

func NewDatum(in interface{}) (d Datum)

NewDatum creates a new Datum from an interface{}.

func NewDecimalDatum 

func NewDecimalDatum(dec mysql.Decimal) (d Datum)

NewDecimalDatum creates a new Datum form a mysql.Decimal value.

func NewDurationDatum 

func NewDurationDatum(dur mysql.Duration) (d Datum)

NewDurationDatum creates a new Datum from a mysql.Duration value.

func NewFloat32Datum 

func NewFloat32Datum(f float32) (d Datum)

NewFloat32Datum creates a new Datum from a float32 value.

func NewFloat64Datum 

func NewFloat64Datum(f float64) (d Datum)

NewFloat64Datum creates a new Datum from a float64 value.

func NewIntDatum 

func NewIntDatum(i int64) (d Datum)

NewIntDatum creates a new Datum from an int64 value.

func NewStringDatum 

func NewStringDatum(s string) (d Datum)

NewStringDatum creates a new Datum from a string.

func NewUintDatum 

func NewUintDatum(i uint64) (d Datum)

NewUintDatum creates a new Datum from an uint64 value.

func (*Datum) Cast 

func (d *Datum) Cast(target *FieldType) (ad Datum, err error)

Cast casts datum to certain types.

func (*Datum) CompareDatum 

func (d *Datum) CompareDatum(ad Datum) (int, error)

CompareDatum compares datum to another datum. TODO: return error properly.

func (*Datum) ConvertTo 

func (d *Datum) ConvertTo(target *FieldType) (Datum, error)

ConvertTo converts a datum to the target field type.

func (*Datum) GetBytes 

func (d *Datum) GetBytes() []byte

GetBytes gets bytes value.

func (*Datum) GetFloat32 

func (d *Datum) GetFloat32() float32

GetFloat32 gets float32 value.

func (*Datum) GetFloat64 

func (d *Datum) GetFloat64() float64

GetFloat64 gets float64 value.

func (*Datum) GetInt64 

func (d *Datum) GetInt64() int64

GetInt64 gets int64 value.

func (*Datum) GetInterface 

func (d *Datum) GetInterface() interface{}

GetInterface gets interface value.

func (*Datum) GetMysqlBit 

func (d *Datum) GetMysqlBit() mysql.Bit

GetMysqlBit gets mysql.Bit value

func (*Datum) GetMysqlDecimal 

func (d *Datum) GetMysqlDecimal() mysql.Decimal

GetMysqlDecimal gets mysql.Decimal value

func (*Datum) GetMysqlDuration 

func (d *Datum) GetMysqlDuration() mysql.Duration

GetMysqlDuration gets mysql.Duration value

func (*Datum) GetMysqlEnum 

func (d *Datum) GetMysqlEnum() mysql.Enum

GetMysqlEnum gets mysql.Enum value

func (*Datum) GetMysqlHex 

func (d *Datum) GetMysqlHex() mysql.Hex

GetMysqlHex gets mysql.Hex value

func (*Datum) GetMysqlSet 

func (d *Datum) GetMysqlSet() mysql.Set

GetMysqlSet gets mysql.Set value

func (*Datum) GetMysqlTime 

func (d *Datum) GetMysqlTime() mysql.Time

GetMysqlTime gets mysql.Time value

func (*Datum) GetRow 

func (d *Datum) GetRow() []Datum

GetRow gets row value.

func (*Datum) GetString 

func (d *Datum) GetString() string

GetString gets string value.

func (*Datum) GetUint64 

func (d *Datum) GetUint64() uint64

GetUint64 gets uint64 value.

func (*Datum) GetValue 

func (d *Datum) GetValue() interface{}

GetValue gets the value of the datum of any kind.

func (*Datum) IsNull 

func (d *Datum) IsNull() bool

IsNull checks if datum is null.

func (*Datum) Kind 

func (d *Datum) Kind() byte

Kind gets the kind of the datum.

func (*Datum) SetBytes 

func (d *Datum) SetBytes(b []byte)

SetBytes sets bytes value to datum.

func (*Datum) SetBytesAsString 

func (d *Datum) SetBytesAsString(b []byte)

SetBytesAsString sets bytes value to datum as string type.

func (*Datum) SetFloat32 

func (d *Datum) SetFloat32(f float32)

SetFloat32 sets float32 value.

func (*Datum) SetFloat64 

func (d *Datum) SetFloat64(f float64)

SetFloat64 sets float64 value.

func (*Datum) SetInt64 

func (d *Datum) SetInt64(i int64)

SetInt64 sets int64 value.

func (*Datum) SetInterface 

func (d *Datum) SetInterface(x interface{})

SetInterface sets interface to datum.

func (*Datum) SetMysqlBit 

func (d *Datum) SetMysqlBit(b mysql.Bit)

SetMysqlBit sets mysql.Bit value

func (*Datum) SetMysqlDecimal 

func (d *Datum) SetMysqlDecimal(b mysql.Decimal)

SetMysqlDecimal sets mysql.Decimal value

func (*Datum) SetMysqlDuration 

func (d *Datum) SetMysqlDuration(b mysql.Duration)

SetMysqlDuration sets mysql.Duration value

func (*Datum) SetMysqlEnum 

func (d *Datum) SetMysqlEnum(b mysql.Enum)

SetMysqlEnum sets mysql.Enum value

func (*Datum) SetMysqlHex 

func (d *Datum) SetMysqlHex(b mysql.Hex)

SetMysqlHex sets mysql.Hex value

func (*Datum) SetMysqlSet 

func (d *Datum) SetMysqlSet(b mysql.Set)

SetMysqlSet sets mysql.Set value

func (*Datum) SetMysqlTime 

func (d *Datum) SetMysqlTime(b mysql.Time)

SetMysqlTime sets mysql.Time value

func (*Datum) SetNull 

func (d *Datum) SetNull()

SetNull sets datum to nil.

func (*Datum) SetRow 

func (d *Datum) SetRow(ds []Datum)

SetRow sets row value.

func (*Datum) SetString 

func (d *Datum) SetString(s string)

SetString sets string value.

func (*Datum) SetUint64 

func (d *Datum) SetUint64(i uint64)

SetUint64 sets uint64 value.

func (*Datum) SetValue 

func (d *Datum) SetValue(val interface{})

SetValue sets any kind of value.

func (*Datum) ToBool 

func (d *Datum) ToBool() (int64, error)

ToBool converts to a bool. We will use 1 for true, and 0 for false.

func (*Datum) ToDecimal 

func (d *Datum) ToDecimal() (mysql.Decimal, error)

ToDecimal converts to a decimal.

func (*Datum) ToFloat64 

func (d *Datum) ToFloat64() (float64, error)

ToFloat64 converts to a float64

func (*Datum) ToInt64 

func (d *Datum) ToInt64() (int64, error)

ToInt64 converts to a int64.

func (*Datum) ToString 

func (d *Datum) ToString() (string, error)

ToString gets the string representation of the datum.

type FieldType 

type FieldType struct {
	Tp      byte
	Flag    uint
	Flen    int
	Decimal int
	Charset string
	Collate string
	// Elems is the element list for enum and set type.
	Elems []string
}

FieldType records field type information.

func DefaultTypeForValue 

func DefaultTypeForValue(value interface{}) *FieldType

DefaultTypeForValue returns the default FieldType for the value.

func NewFieldType 

func NewFieldType(tp byte) *FieldType

NewFieldType returns a FieldType, with a type and other information about field type.

func (*FieldType) CompactStr 

func (ft *FieldType) CompactStr() string

CompactStr only considers Tp/CharsetBin/Flen/Deimal. This is used for showing column type in infoschema.

func (*FieldType) String 

func (ft *FieldType) String() string

String joins the information of FieldType and returns a string.

Source Files

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