github.com/matrixorigin/matrixone@v0.7.0/pkg/sql/plan/function/builtin/unary/length.go (about)

     1  // Copyright 2022 Matrix Origin
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //      http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package unary
    16  
    17  import (
    18  	"github.com/matrixorigin/matrixone/pkg/container/types"
    19  	"github.com/matrixorigin/matrixone/pkg/container/vector"
    20  	"github.com/matrixorigin/matrixone/pkg/vm/process"
    21  )
    22  
    23  func Length(vectors []*vector.Vector, proc *process.Process) (*vector.Vector, error) {
    24  	inputVector := vectors[0]
    25  	resultType := types.Type{Oid: types.T_int64, Size: 8}
    26  	if inputVector.IsScalarNull() {
    27  		return proc.AllocScalarNullVector(resultType), nil
    28  	}
    29  	inputValues := vector.MustStrCols(inputVector)
    30  	if inputVector.IsScalar() {
    31  		ret := vector.NewConstFixed(resultType, inputVector.Length(), int64(len(inputValues[0])), proc.Mp())
    32  		return ret, nil
    33  	} else {
    34  		resultVector, err := proc.AllocVectorOfRows(resultType, int64(len(inputValues)), inputVector.Nsp)
    35  		if err != nil {
    36  			return nil, err
    37  		}
    38  		resultValues := vector.MustTCols[int64](resultVector)
    39  		strLength(inputValues, resultValues)
    40  		return resultVector, nil
    41  	}
    42  }
    43  
    44  func strLength(xs []string, rs []int64) []int64 {
    45  	for i, s := range xs {
    46  		rs[i] = int64(len(s))
    47  	}
    48  	return rs
    49  }