github.com/matrixorigin/matrixone@v1.2.0/pkg/sql/plan/tools.go (about)

     1  // Copyright 2021 - 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 plan
    16  
    17  import (
    18  	"go/constant"
    19  
    20  	"github.com/matrixorigin/matrixone/pkg/sql/parsers/tree"
    21  )
    22  
    23  const (
    24  	moRecursiveLevelCol            = "__mo_recursive_level_col"
    25  	moDefaultRecursionMax          = 100
    26  	moCheckRecursionLevelFun       = "mo_check_level"
    27  	moEnumCastIndexToValueFun      = "cast_index_to_value"
    28  	moEnumCastValueToIndexFun      = "cast_value_to_index"
    29  	moEnumCastIndexValueToIndexFun = "cast_index_value_to_index"
    30  )
    31  
    32  func makeZeroRecursiveLevel() tree.SelectExpr {
    33  	return tree.SelectExpr{
    34  		Expr: tree.NewNumValWithType(constant.MakeInt64(0), "0", false, tree.P_int64),
    35  		As:   tree.NewCStr(moRecursiveLevelCol, 1),
    36  	}
    37  
    38  }
    39  
    40  func makePlusRecursiveLevel(name string) tree.SelectExpr {
    41  	a := tree.SetUnresolvedName(name, moRecursiveLevelCol)
    42  	b := tree.NewNumValWithType(constant.MakeInt64(1), "1", false, tree.P_int64)
    43  	return tree.SelectExpr{
    44  		Expr: tree.NewBinaryExpr(tree.PLUS, a, b),
    45  		As:   tree.NewCStr("", 1),
    46  	}
    47  }