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GeezerVison is showing github.com — sqlparser/analyzer.go at master · skyhee/sqlparser Expand file tree/ Copy pathanalyzer.goMore file actions 343 lines (319 loc) · 8.24 KB / Copy pathanalyzer.goFile metadata and controls343 lines (319 loc) · 8.24 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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 /* Copyright 2017 Google 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 sqlparser // analyzer.go contains utility analysis functions. import ( "errors" "fmt" "strconv" "strings" "unicode" "github.com/xwb1989/sqlparser/dependency/sqltypes" ) // These constants are used to identify the SQL statement type. const ( StmtSelect = iota StmtStream StmtInsert StmtReplace StmtUpdate StmtDelete StmtDDL StmtBegin StmtCommit StmtRollback StmtSet StmtShow StmtUse StmtOther StmtUnknown StmtComment ) // Preview analyzes the beginning of the query using a simpler and faster // textual comparison to identify the statement type. func Preview(sql string) int { trimmed := StripLeadingComments(sql) firstWord := trimmed if end := strings.IndexFunc(trimmed, unicode.IsSpace); end != -1 { firstWord = trimmed[:end] } firstWord = strings.TrimLeftFunc(firstWord, func(r rune) bool { return !unicode.IsLetter(r) }) // Comparison is done in order of priority. loweredFirstWord := strings.ToLower(firstWord) switch loweredFirstWord { case "select": return StmtSelect case "stream": return StmtStream case "insert": return StmtInsert case "replace": return StmtReplace case "update": return StmtUpdate case "delete": return StmtDelete } // For the following statements it is not sufficient to rely // on loweredFirstWord. This is because they are not statements // in the grammar and we are relying on Preview to parse them. // For instance, we don't want: "BEGIN JUNK" to be parsed // as StmtBegin. trimmedNoComments, _ := SplitMarginComments(trimmed) switch strings.ToLower(trimmedNoComments) { case "begin", "start transaction": return StmtBegin case "commit": return StmtCommit case "rollback": return StmtRollback } switch loweredFirstWord { case "create", "alter", "rename", "drop", "truncate": return StmtDDL case "set": return StmtSet case "show": return StmtShow case "use": return StmtUse case "analyze", "describe", "desc", "explain", "repair", "optimize": return StmtOther } if strings.Index(trimmed, "/*!") == 0 { return StmtComment } return StmtUnknown } // StmtType returns the statement type as a string func StmtType(stmtType int) string { switch stmtType { case StmtSelect: return "SELECT" case StmtStream: return "STREAM" case StmtInsert: return "INSERT" case StmtReplace: return "REPLACE" case StmtUpdate: return "UPDATE" case StmtDelete: return "DELETE" case StmtDDL: return "DDL" case StmtBegin: return "BEGIN" case StmtCommit: return "COMMIT" case StmtRollback: return "ROLLBACK" case StmtSet: return "SET" case StmtShow: return "SHOW" case StmtUse: return "USE" case StmtOther: return "OTHER" default: return "UNKNOWN" } } // IsDML returns true if the query is an INSERT, UPDATE or DELETE statement. func IsDML(sql string) bool { switch Preview(sql) { case StmtInsert, StmtReplace, StmtUpdate, StmtDelete: return true } return false } // GetTableName returns the table name from the SimpleTableExpr // only if it's a simple expression. Otherwise, it returns "". func GetTableName(node SimpleTableExpr) TableIdent { if n, ok := node.(TableName); ok && n.Qualifier.IsEmpty() { return n.Name } // sub-select or '.' expression return NewTableIdent("") } // IsColName returns true if the Expr is a *ColName. func IsColName(node Expr) bool { _, ok := node.(*ColName) return ok } // IsValue returns true if the Expr is a string, integral or value arg. // NULL is not considered to be a value. func IsValue(node Expr) bool { switch v := node.(type) { case *SQLVal: switch v.Type { case StrVal, HexVal, IntVal, ValArg: return true } } return false } // IsNull returns true if the Expr is SQL NULL func IsNull(node Expr) bool { switch node.(type) { case *NullVal: return true } return false } // IsSimpleTuple returns true if the Expr is a ValTuple that // contains simple values or if it's a list arg. func IsSimpleTuple(node Expr) bool { switch vals := node.(type) { case ValTuple: for _, n := range vals { if !IsValue(n) { return false } } return true case ListArg: return true } // It's a subquery return false } // NewPlanValue builds a sqltypes.PlanValue from an Expr. func NewPlanValue(node Expr) (sqltypes.PlanValue, error) { switch node := node.(type) { case *SQLVal: switch node.Type { case ValArg: return sqltypes.PlanValue{Key: string(node.Val[1:])}, nil case IntVal: n, err := sqltypes.NewIntegral(string(node.Val)) if err != nil { return sqltypes.PlanValue{}, fmt.Errorf("%v", err) } return sqltypes.PlanValue{Value: n}, nil case StrVal: return sqltypes.PlanValue{Value: sqltypes.MakeTrusted(sqltypes.VarBinary, node.Val)}, nil case HexVal: v, err := node.HexDecode() if err != nil { return sqltypes.PlanValue{}, fmt.Errorf("%v", err) } return sqltypes.PlanValue{Value: sqltypes.MakeTrusted(sqltypes.VarBinary, v)}, nil } case ListArg: return sqltypes.PlanValue{ListKey: string(node[2:])}, nil case ValTuple: pv := sqltypes.PlanValue{ Values: make([]sqltypes.PlanValue, 0, len(node)), } for _, val := range node { innerpv, err := NewPlanValue(val) if err != nil { return sqltypes.PlanValue{}, err } if innerpv.ListKey != "" || innerpv.Values != nil { return sqltypes.PlanValue{}, errors.New("unsupported: nested lists") } pv.Values = append(pv.Values, innerpv) } return pv, nil case *NullVal: return sqltypes.PlanValue{}, nil } return sqltypes.PlanValue{}, fmt.Errorf("expression is too complex '%v'", String(node)) } // StringIn is a convenience function that returns // true if str matches any of the values. func StringIn(str string, values ...string) bool { for _, val := range values { if str == val { return true } } return false } // SetKey is the extracted key from one SetExpr type SetKey struct { Key string Scope string } // ExtractSetValues returns a map of key-value pairs // if the query is a SET statement. Values can be bool, int64 or string. // Since set variable names are case insensitive, all keys are returned // as lower case. func ExtractSetValues(sql string) (keyValues map[SetKey]interface{}, scope string, err error) { stmt, err := Parse(sql) if err != nil { return nil, "", err } setStmt, ok := stmt.(*Set) if !ok { return nil, "", fmt.Errorf("ast did not yield *sqlparser.Set: %T", stmt) } result := make(map[SetKey]interface{}) for _, expr := range setStmt.Exprs { scope := SessionStr key := expr.Name.Lowered() switch { case strings.HasPrefix(key, "@@global."): scope = GlobalStr key = strings.TrimPrefix(key, "@@global.") case strings.HasPrefix(key, "@@session."): key = strings.TrimPrefix(key, "@@session.") case strings.HasPrefix(key, "@@"): key = strings.TrimPrefix(key, "@@") } if strings.HasPrefix(expr.Name.Lowered(), "@@") { if setStmt.Scope != "" && scope != "" { return nil, "", fmt.Errorf("unsupported in set: mixed using of variable scope") } _, out := NewStringTokenizer(key).Scan() key = string(out) } setKey := SetKey{ Key: key, Scope: scope, } switch expr := expr.Expr.(type) { case *SQLVal: switch expr.Type { case StrVal: result[setKey] = strings.ToLower(string(expr.Val)) case IntVal: num, err := strconv.ParseInt(string(expr.Val), 0, 64) if err != nil { return nil, "", err } result[setKey] = num default: return nil, "", fmt.Errorf("invalid value type: %v", String(expr)) } case BoolVal: var val int64 if expr { val = 1 } result[setKey] = val case *ColName: result[setKey] = expr.Name.String() case *NullVal: result[setKey] = nil case *Default: result[setKey] = "default" default: return nil, "", fmt.Errorf("invalid syntax: %s", String(expr)) } } return result, strings.ToLower(setStmt.Scope), nil } |
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