fix: mysql case when (#317)

Author: liuxy0551

src/grammar/mysql/MySqlParser.g4

@@ -2779,8 +2779,8 @@ specificFunction
     | KW_CONVERT '(' expression KW_USING charsetName ')'                            # dataTypeFunctionCall
     | KW_CAST '(' expression KW_AS convertedDataType ')'                            # dataTypeFunctionCall
     | KW_VALUES '(' columnName ')'                                                  # valuesFunctionCall
-    | KW_CASE expression caseFuncAlternative+ (KW_ELSE elseArg=functionArg)? KW_END # caseExpressionFunctionCall
     | KW_CASE caseFuncAlternative+ (KW_ELSE elseArg=functionArg)? KW_END            # caseFunctionCall
+    | KW_CASE expression caseFuncAlternative+ (KW_ELSE elseArg=functionArg)? KW_END # caseExpressionFunctionCall
     | KW_CHAR '(' functionArgs (KW_USING charsetName)? ')'                          # charFunctionCall
     | KW_POSITION '(' (positionString=stringLiteral | positionExpression=expression) KW_IN (
         inString=stringLiteral

src/lib/mysql/MySqlParser.interp

@@ -43810,49 +43810,49 @@ export class MySqlParser extends SQLParserBase {
                 }
                 break;
             case 7:
-                localContext = new CaseExpressionFunctionCallContext(localContext);
+                localContext = new CaseFunctionCallContext(localContext);
                 this.enterOuterAlt(localContext, 7);
                 {
                 this.state = 7424;
                 this.match(MySqlParser.KW_CASE);
-                this.state = 7425;
-                this.expression(0);
-                this.state = 7427;
+                this.state = 7426;
                 this.errorHandler.sync(this);
                 _la = this.tokenStream.LA(1);
                 do {
                     {
                     {
-                    this.state = 7426;
+                    this.state = 7425;
                     this.caseFuncAlternative();
                     }
                     }
-                    this.state = 7429;
+                    this.state = 7428;
                     this.errorHandler.sync(this);
                     _la = this.tokenStream.LA(1);
                 } while (_la === 191);
-                this.state = 7433;
+                this.state = 7432;
                 this.errorHandler.sync(this);
                 _la = this.tokenStream.LA(1);
                 if (_la === 53) {
                     {
-                    this.state = 7431;
+                    this.state = 7430;
                     this.match(MySqlParser.KW_ELSE);
-                    this.state = 7432;
-                    (localContext as CaseExpressionFunctionCallContext)._elseArg = this.functionArg();
+                    this.state = 7431;
+                    (localContext as CaseFunctionCallContext)._elseArg = this.functionArg();
                     }
                 }
 
-                this.state = 7435;
+                this.state = 7434;
                 this.match(MySqlParser.KW_END);
                 }
                 break;
             case 8:
-                localContext = new CaseFunctionCallContext(localContext);
+                localContext = new CaseExpressionFunctionCallContext(localContext);
                 this.enterOuterAlt(localContext, 8);
                 {
-                this.state = 7437;
+                this.state = 7436;
                 this.match(MySqlParser.KW_CASE);
+                this.state = 7437;
+                this.expression(0);
                 this.state = 7439;
                 this.errorHandler.sync(this);
                 _la = this.tokenStream.LA(1);
@@ -43875,7 +43875,7 @@ export class MySqlParser extends SQLParserBase {
                     this.state = 7443;
                     this.match(MySqlParser.KW_ELSE);
                     this.state = 7444;
-                    (localContext as CaseFunctionCallContext)._elseArg = this.functionArg();
+                    (localContext as CaseExpressionFunctionCallContext)._elseArg = this.functionArg();
                     }
                 }
 
@@ -48262,8 +48262,8 @@ export class MySqlParser extends SQLParserBase {
         7388,8,380,1,380,3,380,7391,8,380,1,381,1,381,1,381,3,381,7396,8,
         381,1,381,1,381,1,381,1,381,1,381,1,381,1,381,1,381,1,381,1,381,
         1,381,1,381,1,381,1,381,1,381,1,381,1,381,1,381,1,381,1,381,1,381,
-        1,381,1,381,1,381,1,381,1,381,1,381,1,381,1,381,1,381,4,381,7428,
-        8,381,11,381,12,381,7429,1,381,1,381,3,381,7434,8,381,1,381,1,381,
+        1,381,1,381,1,381,1,381,1,381,1,381,1,381,1,381,4,381,7427,8,381,
+        11,381,12,381,7428,1,381,1,381,3,381,7433,8,381,1,381,1,381,1,381,
         1,381,1,381,4,381,7440,8,381,11,381,12,381,7441,1,381,1,381,3,381,
         7446,8,381,1,381,1,381,1,381,1,381,1,381,1,381,1,381,3,381,7455,
         8,381,1,381,1,381,1,381,1,381,1,381,1,381,3,381,7463,8,381,1,381,
@@ -50909,11 +50909,11 @@ export class MySqlParser extends SQLParserBase {
         7414,5,866,0,0,7414,7415,3,800,400,0,7415,7416,5,13,0,0,7416,7417,
         3,726,363,0,7417,7418,5,867,0,0,7418,7572,1,0,0,0,7419,7420,5,189,
         0,0,7420,7421,5,866,0,0,7421,7422,3,658,329,0,7422,7423,5,867,0,
-        0,7423,7572,1,0,0,0,7424,7425,5,23,0,0,7425,7427,3,800,400,0,7426,
-        7428,3,764,382,0,7427,7426,1,0,0,0,7428,7429,1,0,0,0,7429,7427,1,
-        0,0,0,7429,7430,1,0,0,0,7430,7433,1,0,0,0,7431,7432,5,53,0,0,7432,
-        7434,3,798,399,0,7433,7431,1,0,0,0,7433,7434,1,0,0,0,7434,7435,1,
-        0,0,0,7435,7436,5,378,0,0,7436,7572,1,0,0,0,7437,7439,5,23,0,0,7438,
+        0,7423,7572,1,0,0,0,7424,7426,5,23,0,0,7425,7427,3,764,382,0,7426,
+        7425,1,0,0,0,7427,7428,1,0,0,0,7428,7426,1,0,0,0,7428,7429,1,0,0,
+        0,7429,7432,1,0,0,0,7430,7431,5,53,0,0,7431,7433,3,798,399,0,7432,
+        7430,1,0,0,0,7432,7433,1,0,0,0,7433,7434,1,0,0,0,7434,7435,5,378,
+        0,0,7435,7572,1,0,0,0,7436,7437,5,23,0,0,7437,7439,3,800,400,0,7438,
         7440,3,764,382,0,7439,7438,1,0,0,0,7440,7441,1,0,0,0,7441,7439,1,
         0,0,0,7441,7442,1,0,0,0,7442,7445,1,0,0,0,7443,7444,5,53,0,0,7444,
         7446,3,798,399,0,7445,7443,1,0,0,0,7445,7446,1,0,0,0,7446,7447,1,
@@ -50961,7 +50961,7 @@ export class MySqlParser extends SQLParserBase {
         7568,3,288,144,0,7567,7566,1,0,0,0,7567,7568,1,0,0,0,7568,7569,1,
         0,0,0,7569,7570,5,867,0,0,7570,7572,1,0,0,0,7571,7392,1,0,0,0,7571,
         7397,1,0,0,0,7571,7398,1,0,0,0,7571,7405,1,0,0,0,7571,7412,1,0,0,
-        0,7571,7419,1,0,0,0,7571,7424,1,0,0,0,7571,7437,1,0,0,0,7571,7449,
+        0,7571,7419,1,0,0,0,7571,7424,1,0,0,0,7571,7436,1,0,0,0,7571,7449,
         1,0,0,0,7571,7458,1,0,0,0,7571,7471,1,0,0,0,7571,7491,1,0,0,0,7571,
         7505,1,0,0,0,7571,7518,1,0,0,0,7571,7537,1,0,0,0,7571,7547,1,0,0,
         0,7571,7554,1,0,0,0,7572,763,1,0,0,0,7573,7574,5,191,0,0,7574,7575,
@@ -51211,7 +51211,7 @@ export class MySqlParser extends SQLParserBase {
         7095,7098,7103,7106,7110,7115,7120,7125,7130,7133,7138,7143,7148,
         7154,7159,7164,7169,7173,7176,7181,7185,7189,7197,7204,7208,7213,
         7218,7222,7224,7227,7243,7253,7263,7272,7281,7288,7295,7303,7311,
-        7323,7330,7340,7345,7348,7353,7356,7378,7387,7390,7395,7429,7433,
+        7323,7330,7340,7345,7348,7353,7356,7378,7387,7390,7395,7428,7432,
         7441,7445,7454,7462,7467,7475,7480,7485,7487,7496,7501,7509,7514,
         7522,7530,7533,7543,7561,7564,7567,7571,7584,7592,7596,7601,7606,
         7612,7617,7621,7626,7631,7636,7646,7649,7653,7657,7664,7668,7697,

src/lib/mysql/MySqlParser.ts

@@ -605,8 +605,8 @@ import { SimpleFunctionCallContext } from "./MySqlParser.js";
 import { CurrentUserContext } from "./MySqlParser.js";
 import { DataTypeFunctionCallContext } from "./MySqlParser.js";
 import { ValuesFunctionCallContext } from "./MySqlParser.js";
-import { CaseExpressionFunctionCallContext } from "./MySqlParser.js";
 import { CaseFunctionCallContext } from "./MySqlParser.js";
+import { CaseExpressionFunctionCallContext } from "./MySqlParser.js";
 import { CharFunctionCallContext } from "./MySqlParser.js";
 import { PositionFunctionCallContext } from "./MySqlParser.js";
 import { SubstrFunctionCallContext } from "./MySqlParser.js";
@@ -7159,29 +7159,29 @@ export class MySqlParserListener implements ParseTreeListener {
      */
     exitValuesFunctionCall?: (ctx: ValuesFunctionCallContext) => void;
     /**
-     * Enter a parse tree produced by the `caseExpressionFunctionCall`
+     * Enter a parse tree produced by the `caseFunctionCall`
      * labeled alternative in `MySqlParser.specificFunction`.
      * @param ctx the parse tree
      */
-    enterCaseExpressionFunctionCall?: (ctx: CaseExpressionFunctionCallContext) => void;
+    enterCaseFunctionCall?: (ctx: CaseFunctionCallContext) => void;
     /**
-     * Exit a parse tree produced by the `caseExpressionFunctionCall`
+     * Exit a parse tree produced by the `caseFunctionCall`
      * labeled alternative in `MySqlParser.specificFunction`.
      * @param ctx the parse tree
      */
-    exitCaseExpressionFunctionCall?: (ctx: CaseExpressionFunctionCallContext) => void;
+    exitCaseFunctionCall?: (ctx: CaseFunctionCallContext) => void;
     /**
-     * Enter a parse tree produced by the `caseFunctionCall`
+     * Enter a parse tree produced by the `caseExpressionFunctionCall`
      * labeled alternative in `MySqlParser.specificFunction`.
      * @param ctx the parse tree
      */
-    enterCaseFunctionCall?: (ctx: CaseFunctionCallContext) => void;
+    enterCaseExpressionFunctionCall?: (ctx: CaseExpressionFunctionCallContext) => void;
     /**
-     * Exit a parse tree produced by the `caseFunctionCall`
+     * Exit a parse tree produced by the `caseExpressionFunctionCall`
      * labeled alternative in `MySqlParser.specificFunction`.
      * @param ctx the parse tree
      */
-    exitCaseFunctionCall?: (ctx: CaseFunctionCallContext) => void;
+    exitCaseExpressionFunctionCall?: (ctx: CaseExpressionFunctionCallContext) => void;
     /**
      * Enter a parse tree produced by the `charFunctionCall`
      * labeled alternative in `MySqlParser.specificFunction`.

src/lib/mysql/MySqlParserListener.ts

@@ -605,8 +605,8 @@ import { SimpleFunctionCallContext } from "./MySqlParser.js";
 import { CurrentUserContext } from "./MySqlParser.js";
 import { DataTypeFunctionCallContext } from "./MySqlParser.js";
 import { ValuesFunctionCallContext } from "./MySqlParser.js";
-import { CaseExpressionFunctionCallContext } from "./MySqlParser.js";
 import { CaseFunctionCallContext } from "./MySqlParser.js";
+import { CaseExpressionFunctionCallContext } from "./MySqlParser.js";
 import { CharFunctionCallContext } from "./MySqlParser.js";
 import { PositionFunctionCallContext } from "./MySqlParser.js";
 import { SubstrFunctionCallContext } from "./MySqlParser.js";
@@ -4522,19 +4522,19 @@ export class MySqlParserVisitor<Result> extends AbstractParseTreeVisitor<Result>
      */
     visitValuesFunctionCall?: (ctx: ValuesFunctionCallContext) => Result;
     /**
-     * Visit a parse tree produced by the `caseExpressionFunctionCall`
+     * Visit a parse tree produced by the `caseFunctionCall`
      * labeled alternative in `MySqlParser.specificFunction`.
      * @param ctx the parse tree
      * @return the visitor result
      */
-    visitCaseExpressionFunctionCall?: (ctx: CaseExpressionFunctionCallContext) => Result;
+    visitCaseFunctionCall?: (ctx: CaseFunctionCallContext) => Result;
     /**
-     * Visit a parse tree produced by the `caseFunctionCall`
+     * Visit a parse tree produced by the `caseExpressionFunctionCall`
      * labeled alternative in `MySqlParser.specificFunction`.
      * @param ctx the parse tree
      * @return the visitor result
      */
-    visitCaseFunctionCall?: (ctx: CaseFunctionCallContext) => Result;
+    visitCaseExpressionFunctionCall?: (ctx: CaseExpressionFunctionCallContext) => Result;
     /**
      * Visit a parse tree produced by the `charFunctionCall`
      * labeled alternative in `MySqlParser.specificFunction`.

src/lib/mysql/MySqlParserVisitor.ts

@@ -5,6 +5,7 @@ const mysql = new MySQL();
 
 const features = {
     call: readSQL(__dirname, 'call.sql'),
+    case: readSQL(__dirname, 'case.sql'),
     delete: readSQL(__dirname, 'delete.sql'),
     do: readSQL(__dirname, 'do.sql'),
     handler: readSQL(__dirname, 'handler.sql'),

test/parser/mysql/syntax/dml.test.ts

@@ -0,0 +1,63 @@
+-- https://dev.mysql.com/doc/refman/5.7/en/case.html
+
+
+/* CASE case_value
+    WHEN when_value THEN statement_list
+    [WHEN when_value THEN statement_list] ...
+    [ELSE statement_list]
+END CASE
+
+or
+
+CASE
+    WHEN search_condition THEN statement_list
+    [WHEN search_condition THEN statement_list] ...
+    [ELSE statement_list]
+END CASE */
+
+
+SELECT
+    id,
+    CASE
+        WHEN age = 18 THEN '成年'
+        WHEN age = 60 THEN '老年'
+        ELSE '未知'
+    END AS name
+FROM people;
+
+SELECT
+    id,
+    name,
+    score,
+    CASE
+        WHEN score >= 90 THEN 'A'
+        WHEN score >= 80 THEN 'B'
+        WHEN score >= 70 THEN 'C'
+        WHEN score >= 60 THEN 'D'
+        ELSE 'F'
+    END AS grade
+FROM students;
+
+SELECT
+    id,
+    name,
+    salary,
+    CASE salary
+        WHEN 1000 THEN 'Low'
+        WHEN 2000 THEN 'Medium'
+        WHEN 3000 THEN 'High'
+        ELSE 'Unknown'
+    END AS salary_grade
+FROM employees;
+
+SELECT
+    id,
+    name,
+    salary,
+    CASE
+        WHEN salary < 1000 THEN 'Low'
+        WHEN salary >= 1000 AND salary < 3000 THEN 'Medium'
+        WHEN salary >= 3000 THEN 'High'
+        ELSE 'Unknown'
+    END AS salary_grade
+FROM employees;