                     ----------  Having_Clause  ----------

   HAVING ˤϡ롼פ쥯Ȥ뤿ꤷޤ
 SELECTޥɤǺǤ⿼Ҥˤʤä롼פŬѤ졢쥯Ȥ줿
 Ƥ°롼פˤʤäƤ뤫ؿavg, max ʤɡˤΤȤˤȤ
 뤳ȤǤޤ
   HAVING ɽʤ "true" 뤤 "false" Τɤ餫ɾ
 ɽʤޤ

   HAVING  "and"  "or" ѤƷ礷ɽȤȤǤޤ

 ιʸ

        having |B_EXPR           |
               |(B_EXPR)         |
               |B_EXPR or B_EXPR |
               |B_EXPR and B_EXPR|
               |not B_EXPR       |

   Ĥɽ "and" Ƿ礹硢Τɽ true Ȥʤ뤿ˤ
 ξɽ true ǤʤФʤޤ

   Ĥɽ "or" Ƿ礹硢Τɽ true Ȥʤ뤿ˤ
 뤤ϡξɽ true ǤʤФʤޤ

   ξ˻ꤵ줿硢"and" 黻Ҥ "or" 黻Ҥͥ褷ޤ

   HAVING ϼηɽޤळȤǤޤ

        | GP_EXPR [ |is      | ] GP_CONDITION |
        |           |[is] not|                |
        |                                     |
        | null GP_EXPR                        |

        GP_EXPR : |GP_ATTR_NAME                         |
                  |STRING                               |
                  |NUMBER                               |
                  |GP_FUNCTION                          |
                  |(GP_EXPR)                            |
                  |convert GP_EXPR [to] DATATYPE        |
                  |convert GP_EXPR [to] generic DATATYPE|
                  |GP_EXPR convert to DATATYPE          |
                  |GP_EXPR convert [to] generic DATATYPE|
                  |GP_EXPR OPERATOR GP_EXPR             |
                  |GP_EXPR OPERATOR                     |
                  |OPERATOR GP_EXPR                     |
                  |BUILT_IN_FUNCTION                    |
                  |USER_DEFINED_FUNCTION                |

   GP_ATTR ˤ "group by" ˸°Ρ줫ꤷޤ°  "group by" ˸줿顢ƥ롼פФ뤽ͤȤޤ

   GP_FUNCTION ϡ"group by" ˸ʤ°ˤĤƤΥ롼״ؿǤ
   "count", "avg", "max", "min", "sum" Τ褦ʥ롼״ؿ롼ŬѤ
 ޤ

   OPERATOR  BUILT_IN_FUNCTION ˤĤƤ EXPR 򻲾ȤƤ

        GP_CONDITION :
                | | =  | GP_EXPR                                            |
                | | != |                                                    |
                | | >  |                                                    |
                | | >= |                                                    |
                | | <  |                                                    |
                | | <= |                                                    |
                |                                                           |
                | | like    | PATTERN                                       |
                | | match   |                                               |
                | | !match  |                                               |
                | | smatch  |                                               |
                | | !smatch |                                               |
                |                                                           |
                | [ | =  | ] null                                           |
                |   | != |                                                  |
                |                                                           |
                | between GP_EXPR [|exclusive|] [and] GP_EXPR [|exclusive|] |
                |                  |inclusive|                 |inclusive|  |
                |                                                           |
                | range GP_EXPR [|exclusive|] [to] GP_EXPR [|exclusive|]    |
                |                |inclusive|                |inclusive|     |

   "between ... and" ϡ"range ... to" Ʊư򤷤ޤͤˤϾάͤȤơ inclusiveʴޤޤˤꤷޤ롼פξˤϡˤʤ
 ƤʤФʤޤ

   HAVING Υѥޥå󥰤ˤĤƤϡ WHERE 򻲾ȤƤ

   ˾ɬפʾϰʲ˼ޥɤϤƤ

                help select;
                help where_clause;
