sql2.y

%{
#include "sql2hdr.h"
%}

  /* symbolic tokens */

%union {
  int intval;
  double floatval;
  char *strval;
  int subtok;
}
  
%token NAME
%token STRING
%token INTNUM APPROXNUM

  /* operators */

%left OR
%left AND
%left NOT
%left <subtok> COMPARISON /* = <> < > <= >= */
%left '+' '-'
%left '*' '/'
%nonassoc UMINUS

  /* literal keyword tokens */

%token ALL AMMSC ANY AS ASC AUTHORIZATION BETWEEN BY
%token CHARACTER CHECK CLOSE COMMIT CONTINUE CREATE CURRENT
%token CURSOR DECIMAL DECLARE DEFAULT DELETE DESC DISTINCT DOUBLE
%token ESCAPE EXISTS FETCH FLOAT FOR FOREIGN FOUND FROM GOTO
%token GRANT GROUP HAVING IN INDICATOR INSERT INTEGER INTO
%token IS KEY LANGUAGE LIKE NULLX NUMERIC OF ON OPEN OPTION
%token ORDER PARAMETER PRECISION PRIMARY PRIVILEGES PROCEDURE
%token PUBLIC REAL REFERENCES ROLLBACK SCHEMA SELECT SET
%token SMALLINT SOME SQLCODE SQLERROR TABLE TO UNION
%token UNIQUE UPDATE USER VALUES VIEW WHENEVER WHERE WITH WORK

%%

sql_list:
    sql ';'  { end_sql(); }
  |  sql_list sql ';' { end_sql(); }
  ;


  /* schema definition language */
sql:    schema
  ;
  
schema:
    CREATE SCHEMA AUTHORIZATION user opt_schema_element_list
  ;

opt_schema_element_list:
    /* empty */
  |  schema_element_list
  ;

schema_element_list:
    schema_element
  |  schema_element_list schema_element
  ;

schema_element:
    base_table_def
  |  view_def
  |  privilege_def
  ;

base_table_def:
    CREATE TABLE table '(' base_table_element_commalist ')'
  ;

base_table_element_commalist:
    base_table_element
  |  base_table_element_commalist ',' base_table_element
  ;

base_table_element:
    column_def
  |  table_constraint_def
  ;

column_def:
    column data_type column_def_opt_list
  ;

column_def_opt_list:
    /* empty */
  |  column_def_opt_list column_def_opt
  ;

column_def_opt:
    NOT NULLX
  |  NOT NULLX UNIQUE
  |  NOT NULLX PRIMARY KEY
  |  DEFAULT literal
  |  DEFAULT NULLX
  |  DEFAULT USER
  |  CHECK '(' search_condition ')'
  |  REFERENCES table
  |  REFERENCES table '(' column_commalist ')'
  ;

table_constraint_def:
    UNIQUE '(' column_commalist ')'
  |  PRIMARY KEY '(' column_commalist ')'
  |  FOREIGN KEY '(' column_commalist ')'
      REFERENCES table 
  |  FOREIGN KEY '(' column_commalist ')'
      REFERENCES table '(' column_commalist ')'
  |  CHECK '(' search_condition ')'
  ;

column_commalist:
    column
  |  column_commalist ',' column
  ;

view_def:
    CREATE VIEW table opt_column_commalist
    AS query_spec opt_with_check_option
  ;
  
opt_with_check_option:
    /* empty */
  |  WITH CHECK OPTION
  ;

opt_column_commalist:
    /* empty */
  |  '(' column_commalist ')'
  ;

privilege_def:
    GRANT privileges ON table TO grantee_commalist
    opt_with_grant_option
  ;

opt_with_grant_option:
    /* empty */
  |  WITH GRANT OPTION
  ;

privileges:
    ALL PRIVILEGES
  |  ALL
  |  operation_commalist
  ;

operation_commalist:
    operation
  |  operation_commalist ',' operation
  ;

operation:
    SELECT
  |  INSERT
  |  DELETE
  |  UPDATE opt_column_commalist
  |  REFERENCES opt_column_commalist
  ;


grantee_commalist:
    grantee
  |  grantee_commalist ',' grantee
  ;

grantee:
    PUBLIC
  |  user
  ;

  /* cursor definition */
sql:
    cursor_def
  ;


cursor_def:
    DECLARE cursor CURSOR FOR query_exp opt_order_by_clause
  ;

opt_order_by_clause:
    /* empty */
  |  ORDER BY ordering_spec_commalist
  ;

ordering_spec_commalist:
    ordering_spec
  |  ordering_spec_commalist ',' ordering_spec
  ;

ordering_spec:
    INTNUM opt_asc_desc
  |  column_ref opt_asc_desc
  ;

opt_asc_desc:
    /* empty */
  |  ASC
  |  DESC
  ;

  /* manipulative statements */

sql:    manipulative_statement
  ;

manipulative_statement:
    close_statement
  |  commit_statement
  |  delete_statement_positioned
  |  delete_statement_searched
  |  fetch_statement
  |  insert_statement
  |  open_statement
  |  rollback_statement
  |  select_statement
  |  update_statement_positioned
  |  update_statement_searched
  ;

close_statement:
    CLOSE cursor
  ;

commit_statement:
    COMMIT WORK
  ;

delete_statement_positioned:
    DELETE FROM table WHERE CURRENT OF cursor
  ;

delete_statement_searched:
    DELETE FROM table opt_where_clause
  ;

fetch_statement:
    FETCH cursor INTO target_commalist
  ;

insert_statement:
    INSERT INTO table opt_column_commalist values_or_query_spec
  ;

values_or_query_spec:
    VALUES '(' insert_atom_commalist ')'
  |  query_spec
  ;

insert_atom_commalist:
    insert_atom
  |  insert_atom_commalist ',' insert_atom
  ;

insert_atom:
    atom
  |  NULLX
  ;

open_statement:
    OPEN cursor
  ;

rollback_statement:
    ROLLBACK WORK
  ;

select_statement:
    SELECT opt_all_distinct selection
    INTO target_commalist
    table_exp
  ;

opt_all_distinct:
    /* empty */
  |  ALL
  |  DISTINCT
  ;

update_statement_positioned:
    UPDATE table SET assignment_commalist
    WHERE CURRENT OF cursor
  ;

assignment_commalist:
  |  assignment
  |  assignment_commalist ',' assignment
  ;

assignment:
    column '=' scalar_exp
  |  column '=' NULLX
  ;

update_statement_searched:
    UPDATE table SET assignment_commalist opt_where_clause
  ;

target_commalist:
    target
  |  target_commalist ',' target
  ;

target:
    parameter_ref
  ;

opt_where_clause:
    /* empty */
  |  where_clause
  ;

  /* query expressions */

query_exp:
    query_term
  |  query_exp UNION query_term
  |  query_exp UNION ALL query_term
  ;

query_term:
    query_spec
  |  '(' query_exp ')'
  ;

query_spec:
    SELECT opt_all_distinct selection table_exp
  ;

selection:
    scalar_exp_commalist
  |  '*'
  ;

table_exp:
    from_clause
    opt_where_clause
    opt_group_by_clause
    opt_having_clause
  ;

from_clause:
    FROM table_ref_commalist
  ;

table_ref_commalist:
    table_ref
  |  table_ref_commalist ',' table_ref
  ;

table_ref:
    table 
  |  table range_variable
  ;

where_clause:
    WHERE search_condition
  ;

opt_group_by_clause:
    /* empty */
  |  GROUP BY column_ref_commalist
  ;

column_ref_commalist:
    column_ref
  |  column_ref_commalist ',' column_ref
  ;

opt_having_clause:
    /* empty */
  |  HAVING search_condition
  ;

  /* search conditions */

search_condition:
  |  search_condition OR search_condition
  |  search_condition AND search_condition
  |  NOT search_condition
  |  '(' search_condition ')'
  |  predicate
  ;

predicate:
    comparison_predicate
  |  between_predicate
  |  like_predicate
  |  test_for_null
  |  in_predicate
  |  all_or_any_predicate
  |  existence_test
  ;

comparison_predicate:
    scalar_exp COMPARISON scalar_exp
  |  scalar_exp COMPARISON subquery
  ;

between_predicate:
    scalar_exp NOT BETWEEN scalar_exp AND scalar_exp
  |  scalar_exp BETWEEN scalar_exp AND scalar_exp
  ;

like_predicate:
    scalar_exp NOT LIKE atom opt_escape
  |  scalar_exp LIKE atom opt_escape
  ;

opt_escape:
    /* empty */
  |  ESCAPE atom
  ;

test_for_null:
    column_ref IS NOT NULLX
  |  column_ref IS NULLX
  ;

in_predicate:
    scalar_exp NOT IN '(' subquery ')'
  |  scalar_exp IN '(' subquery ')'
  |  scalar_exp NOT IN '(' atom_commalist ')'
  |  scalar_exp IN '(' atom_commalist ')'
  ;

atom_commalist:
    atom
  |  atom_commalist ',' atom
  ;

all_or_any_predicate:
    scalar_exp COMPARISON any_all_some subquery
  ;
      
any_all_some:
    ANY
  |  ALL
  |  SOME
  ;

existence_test:
    EXISTS subquery
  ;

subquery:
    '(' SELECT opt_all_distinct selection table_exp ')'
  ;

  /* scalar expressions */

scalar_exp:
    scalar_exp '+' scalar_exp
  |  scalar_exp '-' scalar_exp
  |  scalar_exp '*' scalar_exp
  |  scalar_exp '/' scalar_exp
  |  '+' scalar_exp %prec UMINUS
  |  '-' scalar_exp %prec UMINUS
  |  atom
  |  column_ref
  |  function_ref
  |  '(' scalar_exp ')'
  ;

scalar_exp_commalist:
    scalar_exp
  |  scalar_exp_commalist ',' scalar_exp
  ;

atom:
    parameter_ref
  |  literal
  |  USER
  ;

parameter_ref:
    parameter
  |  parameter parameter
  |  parameter INDICATOR parameter
  ;

function_ref:
    AMMSC '(' '*' ')'
  |  AMMSC '(' DISTINCT column_ref ')'
  |  AMMSC '(' ALL scalar_exp ')'
  |  AMMSC '(' scalar_exp ')'
  ;

literal:
    STRING
  |  INTNUM
  |  APPROXNUM
  ;

  /* miscellaneous */

table:
    NAME
  |  NAME '.' NAME
  ;

column_ref:
    NAME
  |  NAME '.' NAME  /* needs semantics */
  |  NAME '.' NAME '.' NAME
  ;

    /* data types */

data_type:
    CHARACTER
  |  CHARACTER '(' INTNUM ')'
  |  NUMERIC
  |  NUMERIC '(' INTNUM ')'
  |  NUMERIC '(' INTNUM ',' INTNUM ')'
  |  DECIMAL
  |  DECIMAL '(' INTNUM ')'
  |  DECIMAL '(' INTNUM ',' INTNUM ')'
  |  INTEGER
  |  SMALLINT
  |  FLOAT
  |  FLOAT '(' INTNUM ')'
  |  REAL
  |  DOUBLE PRECISION
  ;

  /* the various things you can name */

column:    NAME
  ;

cursor:    NAME
  ;

parameter:
    PARAMETER  /* :name handled in parser */
  ;

range_variable:  NAME
  ;

user:    NAME
  ;

  /* embedded condition things */
sql:    WHENEVER NOT FOUND when_action
  |  WHENEVER SQLERROR when_action
  ;

when_action:  GOTO NAME
  |  CONTINUE
  ;
%%