Files
tidb/pkg/expression/builtin_ilike.go

114 lines
3.3 KiB
Go

// Copyright 2023 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,
// 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 expression
import (
"github.com/pingcap/tidb/pkg/types"
"github.com/pingcap/tidb/pkg/util/chunk"
"github.com/pingcap/tidb/pkg/util/collate"
"github.com/pingcap/tidb/pkg/util/intest"
"github.com/pingcap/tidb/pkg/util/stringutil"
"github.com/pingcap/tipb/go-tipb"
)
var (
_ functionClass = &ilikeFunctionClass{}
)
var (
_ builtinFunc = &builtinIlikeSig{}
)
type ilikeFunctionClass struct {
baseFunctionClass
}
func (c *ilikeFunctionClass) getFunction(ctx BuildContext, args []Expression) (builtinFunc, error) {
if err := c.verifyArgs(args); err != nil {
return nil, err
}
argTp := []types.EvalType{types.ETString, types.ETString, types.ETInt}
bf, err := newBaseBuiltinFuncWithTp(ctx, c.funcName, args, types.ETInt, argTp...)
if err != nil {
return nil, err
}
bf.tp.SetFlen(1)
sig := &builtinIlikeSig{baseBuiltinFunc: bf}
sig.setPbCode(tipb.ScalarFuncSig_IlikeSig)
return sig, nil
}
type builtinIlikeSig struct {
baseBuiltinFunc
// pattern is not serialized with builtinIlikeSig, treat them as a cache to accelerate
// the evaluation of builtinIlikeSig.
patternCache builtinFuncCache[collate.WildcardPattern]
}
func (b *builtinIlikeSig) Clone() builtinFunc {
newSig := &builtinIlikeSig{}
newSig.cloneFrom(&b.baseBuiltinFunc)
return newSig
}
// evalInt evals a builtinIlikeSig.
func (b *builtinIlikeSig) evalInt(ctx EvalContext, row chunk.Row) (int64, bool, error) {
valStr, isNull, err := b.args[0].EvalString(ctx, row)
if isNull || err != nil {
return 0, isNull, err
}
patternStr, isNull, err := b.args[1].EvalString(ctx, row)
if isNull || err != nil {
return 0, isNull, err
}
escape, isNull, err := b.args[2].EvalInt(ctx, row)
if isNull || err != nil {
return 0, isNull, err
}
valStrBytes := []byte(valStr)
patternStrBytes := []byte(patternStr)
stringutil.LowerOneString(valStrBytes)
if stringutil.IsUpperASCII(byte(escape)) || stringutil.IsLowerASCII(byte(escape)) {
escape = int64(stringutil.LowerOneStringExcludeEscapeChar(patternStrBytes, byte(escape)))
} else {
stringutil.LowerOneString(patternStrBytes)
}
valStr = string(valStrBytes)
patternStr = string(patternStrBytes)
var pattern collate.WildcardPattern
if b.args[1].ConstLevel() >= ConstOnlyInContext && b.args[2].ConstLevel() >= ConstOnlyInContext {
pattern, err = b.patternCache.getOrInitCache(ctx, func() (collate.WildcardPattern, error) {
ret := collate.ConvertAndGetBinCollator(b.collation).Pattern()
ret.Compile(patternStr, byte(escape))
return ret, nil
})
intest.AssertNoError(err)
if err != nil {
return 0, true, err
}
} else {
pattern = collate.ConvertAndGetBinCollator(b.collation).Pattern()
pattern.Compile(patternStr, byte(escape))
}
return boolToInt64(pattern.DoMatch(valStr)), false, nil
}