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GeezerVison is showing github.com — sqlparser/utils.go at master · smlxl/sqlparser
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Expand file tree/ Copy pathutils.goMore file actions 182 lines (166 loc) · 4.73 KB / Copy pathutils.goFile metadata and controls182 lines (166 loc) · 4.73 KB 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 /* Copyright 2020 The Vitess Authors. 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 sqlparser import ( "fmt" "sort" "strings" querypb "vitess.io/vitess/go/vt/proto/query" ) // QueryMatchesTemplates sees if the given query has the same fingerprint as one of the given templates // (one is enough) func (p *Parser) QueryMatchesTemplates(query string, queryTemplates []string) (match bool, err error) { if len(queryTemplates) == 0 { return false, fmt.Errorf("No templates found") } bv := make(map[string]*querypb.BindVariable) normalize := func(q string) (string, error) { q, err := p.NormalizeAlphabetically(q) if err != nil { return "", err } stmt, reservedVars, err := p.Parse2(q) if err != nil { return "", err } err = Normalize(stmt, NewReservedVars("", reservedVars), bv) if err != nil { return "", err } normalized := CanonicalString(stmt) return normalized, nil } normalizedQuery, err := normalize(query) if err != nil { return false, err } for _, template := range queryTemplates { normalizedTemplate, err := normalize(template) if err != nil { return false, err } // compare! if normalizedTemplate == normalizedQuery { return true, nil } } return false, nil } // NormalizeAlphabetically rewrites given query such that: // - WHERE 'AND' expressions are reordered alphabetically func (p *Parser) NormalizeAlphabetically(query string) (normalized string, err error) { stmt, err := p.Parse(query) if err != nil { return normalized, err } var where *Where switch stmt := stmt.(type) { case *Update: where = stmt.Where case *Delete: where = stmt.Where case *Select: where = stmt.Where } if where != nil { andExprs := SplitAndExpression(nil, where.Expr) sort.SliceStable(andExprs, func(i, j int) bool { return String(andExprs[i]) < String(andExprs[j]) }) var newWhere *Where for _, expr := range andExprs { if newWhere == nil { newWhere = &Where{ Type: WhereClause, Expr: expr, } } else { newWhere.Expr = &AndExpr{ Left: newWhere.Expr, Right: expr, } } } switch stmt := stmt.(type) { case *Update: stmt.Where = newWhere case *Delete: stmt.Where = newWhere case *Select: stmt.Where = newWhere } } return String(stmt), nil } // ReplaceTableQualifiers takes a statement's table expressions and // replaces any cases of the provided database name with the // specified replacement name. // Note: both database names provided should be unescaped strings. func (p *Parser) ReplaceTableQualifiers(query, olddb, newdb string) (string, error) { if newdb == olddb { // Nothing to do here. return query, nil } in, err := p.Parse(query) if err != nil { return "", err } oldQualifier := NewIdentifierCS(olddb) newQualifier := NewIdentifierCS(newdb) modified := false upd := Rewrite(in, func(cursor *Cursor) bool { switch node := cursor.Node().(type) { case TableName: if node.Qualifier.NotEmpty() && node.Qualifier.String() == oldQualifier.String() { node.Qualifier = newQualifier cursor.Replace(node) modified = true } case *ShowBasic: // for things like 'show tables from _vt' if node.DbName.NotEmpty() && node.DbName.String() == oldQualifier.String() { node.DbName = newQualifier cursor.Replace(node) modified = true } } return true }, nil) // If we didn't modify anything, return the original query. // This is particularly helpful with unit tests that // execute a query which slightly differs from the parsed // version: e.g. 'where id=1' becomes 'where id = 1'. if modified { return String(upd), nil } return query, nil } // ReplaceTableQualifiersMultiQuery accepts a multi-query string and modifies it // via ReplaceTableQualifiers, one query at a time. func (p *Parser) ReplaceTableQualifiersMultiQuery(multiQuery, olddb, newdb string) (string, error) { queries, err := p.SplitStatementToPieces(multiQuery) if err != nil { return multiQuery, err } var modifiedQueries []string for _, query := range queries { // Replace any provided sidecar database qualifiers with the correct one. query, err := p.ReplaceTableQualifiers(query, olddb, newdb) if err != nil { return query, err } modifiedQueries = append(modifiedQueries, query) } return strings.Join(modifiedQueries, ";"), nil } |
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