浅谈Halo数据库如何适配DB2的语法问题

CREATE TABLE order ( id int,  order VARCHAR(32));INSERT INTO order VALUES(1, 'JACK') ,(2,'LEO');SELECT id, order FROM order;

(instance:DB2INST1, database:):CREATE TABLE order ( id int,  order VARCHAR(32));@DB20000I  The SQL command completed successfully.(instance:DB2INST1, database:):INSERT INTO order VALUES(1, 'JACK') ,(2,'LEO');@DB20000I  The SQL command completed successfully.(instance:DB2INST1, database:):SELECT id, order FROM order;@
ID          ORDER                           ----------- --------------------------------          1 JACK                                      2 LEO                             
  2 record(s) selected.

ERROR:  syntax error at or near "order" at character 14

CREATE TABLE "order" ( id INT,  "order" VARCHAR(32));INSERT INTO "order" VALUES(1, 'JACK') ,(2,'LEO');SELECT id, “order" FROM "order";

PG_KEYWORD("order", ORDER, RESERVED_KEYWORD, AS_LABEL)

list *raw_parser(const char *str, RawParseMode mode)

yyscanner = scanner_init(str, &yyextra.core_yy_extra,                             ScanKeywords, NumScanKeywords);

parser_init(&yyextra);

yyresult = base_yyparse(yyscanner);

int base_yylex(YYSTYPE *lvalp, YYLTYPE *llocp                          , core_yyscan_t yyscanner)

PG_KEYWORD("microsecond", MICROSECOND_P,                     UNRESERVED_KEYWORD, AS_LABEL)

%token <keyword> ... METHOD MICROSECOND_P MINUTE_P ...

/* "Unreserved" keywords --- available for use as any kind of name. */unreserved_keyword:        ABORT_P      | ABSOLUTE_P      ...      | MICROSECOND_P

%type <list> interval_microsecond

interval_microsecond:      MICROSECOND_P        {$$ = list_make1(makeIntConst(INTERVAL_MASK(SECOND), @1));}    ;

SELECT * FROM USER#;

ident_start    [A-Za-z\200-\377_]ident_cont    [A-Za-z\200-\377_0-9\$\#]   /*添加#符号*/

gram.y: error: shift/reduce conflicts: 18 found, 0 expectedgram.y: error: reduce/reduce conflicts: 5 found, 0 expected

/*gram.y中声明方式*/%token ORDER_Q

base_yylex(YYSTYPE *lvalp, YYLTYPE *llocp, core_yyscan_t yyscanner){  base_yy_extra_type *yyextra = base_yyget_extra(yyscanner);  int      cur_token;  int      next_token;  int      cur_token_length;  YYLTYPE    cur_yylloc;
  /* Get next token --- we might already have it */  if (yyextra->have_lookahead)  {    cur_token = yyextra->lookahead_token;    lvalp->core_yystype = yyextra->lookahead_yylval;    *llocp = yyextra->lookahead_yylloc;    if (yyextra->lookahead_end)      *(yyextra->lookahead_end) = yyextra->lookahead_hold_char;    yyextra->have_lookahead = false;  }  else    cur_token = base_core_yylex(&(lvalp->core_yystype), llocp, yyscanner);
  /*   * If this token isn't one that requires lookahead, just return it.  If it   * does, determine the token length.  (We could get that via strlen(), but   * since we have such a small set of possibilities, hardwiring seems   * feasible and more efficient --- at least for the fixed-length cases.)   */  switch (cur_token)  {    case NOT:      cur_token_length = 3;      break;    ...    case ORDER:      cur_token_length = 5;      break;    ...    default:      return cur_token;  }
  /*   * Identify end+1 of current token.  base_core_yylex() has temporarily stored a   * '\0' here, and will undo that when we call it again.  We need to redo   * it to fully revert the lookahead call for error reporting purposes.   */  yyextra->lookahead_end = yyextra->core_yy_extra.scanbuf +    *llocp + cur_token_length;  Assert(*(yyextra->lookahead_end) == '\0');
  /*   * Save and restore *llocp around the call.  It might look like we could   * avoid this by just passing &lookahead_yylloc to base_core_yylex(), but that   * does not work because flex actually holds onto the last-passed pointer   * internally, and will use that for error reporting.  We need any error   * reports to point to the current token, not the next one.   */  cur_yylloc = *llocp;
  /* Get next token, saving outputs into lookahead variables */  next_token = base_core_yylex(&(yyextra->lookahead_yylval), llocp, yyscanner);  yyextra->lookahead_token = next_token;  yyextra->lookahead_yylloc = *llocp;
  *llocp = cur_yylloc;
  /* Now revert the un-truncation of the current token */  yyextra->lookahead_hold_char = *(yyextra->lookahead_end);  *(yyextra->lookahead_end) = '\0';
  yyextra->have_lookahead = true;
  /* Replace cur_token if needed, based on lookahead */  switch (cur_token)  {    case NOT:      /* Replace NOT by NOT_LA if it's followed by BETWEEN, IN, etc */      switch (next_token)      {        case BETWEEN:        case IN_P:        case LIKE:        case ILIKE:        case SIMILAR:          cur_token = NOT_LA;          break;      }      break;
    ...    case ORDER:      if(next_token != BY)        cur_token = ORDER_Q;      break;    ...  }  return cur_token;}

/* Column identifier --- names that can be column, table, etc names. */ColId:    IDENT                  { $$ = $1; }      | unreserved_keyword       { $$ = pstrdup($1); }      | col_name_keyword         { $$ = pstrdup($1); }      | ORDER_Q                  { $$ = pstrdup("order");}    ;

CREATE TABLE order (id int,  order VARCHAR(32));INSERT INTO order VALUES(1, 'JACK'), (2,'LEO');halodb2=# SELECT id, ORDER FROM ORDER; id | order ----+-------  1 | jack  2 | LEO(2 rows)