vitess.io/vitess@v0.16.2/go/vt/vttablet/tabletmanager/vdiff/utils.go (about)

     1  /*
     2  Copyright 2022 The Vitess Authors.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package vdiff
    18  
    19  import (
    20  	"context"
    21  	"fmt"
    22  	"strings"
    23  
    24  	"vitess.io/vitess/go/vt/binlog/binlogplayer"
    25  	"vitess.io/vitess/go/vt/log"
    26  
    27  	"vitess.io/vitess/go/sqltypes"
    28  
    29  	"vitess.io/vitess/go/mysql/collations"
    30  	"vitess.io/vitess/go/vt/vtgate/engine"
    31  )
    32  
    33  // newMergeSorter creates an engine.MergeSort based on the shard streamers and pk columns
    34  func newMergeSorter(participants map[string]*shardStreamer, comparePKs []compareColInfo) *engine.MergeSort {
    35  	prims := make([]engine.StreamExecutor, 0, len(participants))
    36  	for _, participant := range participants {
    37  		prims = append(prims, participant)
    38  	}
    39  	ob := make([]engine.OrderByParams, len(comparePKs))
    40  	for i, cpk := range comparePKs {
    41  		weightStringCol := -1
    42  		// if the collation is nil or unknown, use binary collation to compare as bytes
    43  		if cpk.collation == nil {
    44  			ob[i] = engine.OrderByParams{Col: cpk.colIndex, WeightStringCol: weightStringCol, CollationID: collations.CollationBinaryID}
    45  		} else {
    46  			ob[i] = engine.OrderByParams{Col: cpk.colIndex, WeightStringCol: weightStringCol, CollationID: cpk.collation.ID()}
    47  		}
    48  	}
    49  	return &engine.MergeSort{
    50  		Primitives: prims,
    51  		OrderBy:    ob,
    52  	}
    53  }
    54  
    55  //-----------------------------------------------------------------
    56  // Utility functions
    57  
    58  func encodeString(in string) string {
    59  	var buf strings.Builder
    60  	sqltypes.NewVarChar(in).EncodeSQL(&buf)
    61  	return buf.String()
    62  }
    63  
    64  func pkColsToGroupByParams(pkCols []int) []*engine.GroupByParams {
    65  	var res []*engine.GroupByParams
    66  	for _, col := range pkCols {
    67  		res = append(res, &engine.GroupByParams{KeyCol: col, WeightStringCol: -1})
    68  	}
    69  	return res
    70  }
    71  
    72  func insertVDiffLog(ctx context.Context, dbClient binlogplayer.DBClient, vdiffID int64, message string) {
    73  	query := "insert into _vt.vdiff_log(vdiff_id, message) values (%d, %s)"
    74  	query = fmt.Sprintf(query, vdiffID, encodeString(message))
    75  	if _, err := dbClient.ExecuteFetch(query, 1); err != nil {
    76  		log.Error("Error inserting into _vt.vdiff_log: %v", err)
    77  	}
    78  }
    79  
    80  func stringListContains(lst []string, item string) bool {
    81  	contains := false
    82  	for _, t := range lst {
    83  		if t == item {
    84  			contains = true
    85  			break
    86  		}
    87  	}
    88  	return contains
    89  }