添加三个类型

src/calc.l

@@ -30,6 +30,10 @@ extern YYSTYPE yylval;
 "JOIN"      {return JOIN;}
 "TABLE"		{return TABLE;}
 
+"INT"       {return INT;}
+"FLOAT"     {return FLOAT;}
+"STRING"    {return STRING;}
+
 
 ;		    {return NEWLINE;}
 
@@ -44,6 +48,10 @@ extern YYSTYPE yylval;
 
 "quit"		{return QUIT;}
 
-[a-zA-Z][a-zA-Z0-9]+	{return IDENTIFIER;}
+[a-zA-Z][a-zA-Z0-9]+	{
+    yylval.sv = (char*)malloc(strlen(yytext) + 1);
+    strcpy(yylval.sv, yytext);
+    return IDENTIFIER;
+}
 
 %%