SQLite

  EACH END EXCLUSIVE EXPLAIN FAIL FOR
  IGNORE IMMEDIATE INITIALLY INSTEAD LIKE_KW MATCH NO PLAN
  QUERY KEY OF OFFSET PRAGMA RAISE RECURSIVE RELEASE REPLACE RESTRICT ROW ROWS
  ROLLBACK SAVEPOINT TEMP TRIGGER VACUUM VIEW VIRTUAL WITH WITHOUT
%ifdef SQLITE_OMIT_COMPOUND_SELECT
  EXCEPT INTERSECT UNION
%endif SQLITE_OMIT_COMPOUND_SELECT
%ifndef SQLITE_OMIT_WINDOWFUNC
  CURRENT FOLLOWING PARTITION PRECEDING RANGE UNBOUNDED
%endif SQLITE_OMIT_WINDOWFUNC
  REINDEX RENAME CTIME_KW IF
  .
%wildcard ANY.

// Define operator precedence early so that this is the first occurrence
// of the operator tokens in the grammer.  Keeping the operators together
// causes them to be assigned integer values that are close together,

  A = sqlite3ExprFunction(pParse, 0, &X);
  sqlite3WindowAttach(pParse, A, Z);
}
term(A) ::= CTIME_KW(OP). {
  A = sqlite3ExprFunction(pParse, 0, &OP);
}

































































































expr(A) ::= LP nexprlist(X) COMMA expr(Y) RP. {
  ExprList *pList = sqlite3ExprListAppend(pParse, X, Y);
  A = sqlite3PExpr(pParse, TK_VECTOR, 0, 0);
  if( A ){
    A->x.pList = pList;
  }else{
    sqlite3ExprListDelete(pParse->db, pList);

wqlist(A) ::= nm(X) eidlist_opt(Y) AS LP select(Z) RP. {
  A = sqlite3WithAdd(pParse, 0, &X, Y, Z); /*A-overwrites-X*/
}
wqlist(A) ::= wqlist(A) COMMA nm(X) eidlist_opt(Y) AS LP select(Z) RP. {
  A = sqlite3WithAdd(pParse, A, &X, Y, Z);
}
%endif  SQLITE_OMIT_CTE

//////////////////////// WINDOW FUNCTION EXPRESSIONS /////////////////////////
// These must be at the end of this file. Specifically, the rules that
// introduce tokens WINDOW, OVER and FILTER must appear last. This causes 
// the integer values assigned to these tokens to be larger than all other 
// tokens that may be output by the tokenizer except TK_SPACE and TK_ILLEGAL.
//
%ifndef SQLITE_OMIT_WINDOWFUNC
%type windowdefn_list {Window*}
%destructor windowdefn_list {sqlite3WindowDelete(pParse->db, $$);}
windowdefn_list(A) ::= windowdefn(Z). { A = Z; }
windowdefn_list(A) ::= windowdefn_list(Y) COMMA windowdefn(Z). {
  if( Z ) Z->pNextWin = Y;
  A = Z;
}

%type windowdefn {Window*}
%destructor windowdefn {sqlite3WindowDelete(pParse->db, $$);}
windowdefn(A) ::= nm(X) AS window(Y). {
  if( Y ){
    Y->zName = sqlite3DbStrNDup(pParse->db, X.z, X.n);
  }
  A = Y;
}

%type window {Window*}
%destructor window {sqlite3WindowDelete(pParse->db, $$);}

%type frame_opt {Window*}
%destructor frame_opt {sqlite3WindowDelete(pParse->db, $$);}

%type window_or_nm {Window*}
%destructor window_or_nm {
sqlite3WindowDelete(pParse->db, $$);}

%type part_opt {ExprList*}
%destructor part_opt {sqlite3ExprListDelete(pParse->db, $$);}

%type filter_opt {Expr*}
%destructor filter_opt {sqlite3ExprDelete(pParse->db, $$);}

%type range_or_rows {int}

%type frame_bound {struct FrameBound}
%destructor frame_bound {sqlite3ExprDelete(pParse->db, $$.pExpr);}

window_or_nm(A) ::= window(Z). {A = Z;}
window_or_nm(A) ::= nm(Z). {
  A = (Window*)sqlite3DbMallocZero(pParse->db, sizeof(Window));
  if( A ){
    A->zName = sqlite3DbStrNDup(pParse->db, Z.z, Z.n);
  }
}

window(A) ::= LP part_opt(X) orderby_opt(Y) frame_opt(Z) RP. {
  A = Z;
  if( A ){
    A->pPartition = X;
    A->pOrderBy = Y;
  }
}

part_opt(A) ::= PARTITION BY exprlist(X). { A = X; }
part_opt(A) ::= .                         { A = 0; }

frame_opt(A) ::= .                             { 
  A = sqlite3WindowAlloc(pParse, TK_RANGE, TK_UNBOUNDED, 0, TK_CURRENT, 0);
}
frame_opt(A) ::= range_or_rows(X) frame_bound(Y). { 
  A = sqlite3WindowAlloc(pParse, X, Y.eType, Y.pExpr, TK_CURRENT, 0);
}
frame_opt(A) ::= range_or_rows(X) BETWEEN frame_bound(Y) AND frame_bound(Z). { 
  A = sqlite3WindowAlloc(pParse, X, Y.eType, Y.pExpr, Z.eType, Z.pExpr);
}

range_or_rows(A) ::= RANGE.   { A = TK_RANGE; }
range_or_rows(A) ::= ROWS.    { A = TK_ROWS;  }

frame_bound(A) ::= UNBOUNDED PRECEDING. { A.eType = TK_UNBOUNDED; A.pExpr = 0; }
frame_bound(A) ::= expr(X) PRECEDING.   { A.eType = TK_PRECEDING; A.pExpr = X; }
frame_bound(A) ::= CURRENT ROW.         { A.eType = TK_CURRENT  ; A.pExpr = 0; }
frame_bound(A) ::= expr(X) FOLLOWING.   { A.eType = TK_FOLLOWING; A.pExpr = X; }
frame_bound(A) ::= UNBOUNDED FOLLOWING. { A.eType = TK_UNBOUNDED; A.pExpr = 0; }

%type windowdefn_opt {Window*}
%destructor windowdefn_opt {sqlite3WindowDelete(pParse->db, $$);}
windowdefn_opt(A) ::= . { A = 0; }
windowdefn_opt(A) ::= WINDOW windowdefn_list(B). { A = B; }

%type over_opt {Window*}
%destructor over_opt {sqlite3WindowDelete(pParse->db, $$);}
over_opt(A) ::= . { A = 0; }
over_opt(A) ::= filter_opt(W) OVER window_or_nm(Z). {
  A = Z;
  if( A ) A->pFilter = W;
}

filter_opt(A) ::= .                            { A = 0; }
filter_opt(A) ::= FILTER LP WHERE expr(X) RP.  { A = X; }
%endif // SQLITE_OMIT_WINDOWFUNC

        pNC->nErr++;
      }else if( wrong_num_args ){
        sqlite3ErrorMsg(pParse,"wrong number of arguments to function %.*s()",
             nId, zId);
        pNC->nErr++;
      }
      if( is_agg ){
#ifndef SQLITE_OMIT_WINDOWFUNC
        pNC->ncFlags &= ~(pExpr->pWin ? NC_AllowWin : NC_AllowAgg);
#else
        pNC->ncFlags &= ~NC_AllowAgg;
#endif
      }
      sqlite3WalkExprList(pWalker, pList);
      if( is_agg ){
#ifndef SQLITE_OMIT_WINDOWFUNC
        if( pExpr->pWin ){
          Select *pSel = pNC->pWinSelect;
          sqlite3WalkExprList(pWalker, pExpr->pWin->pPartition);

** The interface to the LEMON-generated parser
*/
#ifndef SQLITE_AMALGAMATION
  void *sqlite3ParserAlloc(void*(*)(u64), Parse*);
  void sqlite3ParserFree(void*, void(*)(void*));
#endif
void sqlite3Parser(void*, int, Token);
int sqlite3ParserFallback(int);
#ifdef YYTRACKMAXSTACKDEPTH
  int sqlite3ParserStackPeak(void*);
#endif

void sqlite3AutoLoadExtensions(sqlite3*);
#ifndef SQLITE_OMIT_LOAD_EXTENSION
  void sqlite3CloseExtensions(sqlite3*);

#endif

/* Make the IdChar function accessible from ctime.c */
#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
int sqlite3IsIdChar(u8 c){ return IdChar(c); }
#endif

#ifndef SQLITE_OMIT_WINDOWFUNC
/*
** Return the id of the next token in string (*pz). Before returning, set
** (*pz) to point to the byte following the parsed token.
*/
static int getToken(const unsigned char **pz){
  const unsigned char *z = *pz;
  int t;                          /* Token type to return */
  do {
    z += sqlite3GetToken(z, &t);
  }while( t==TK_SPACE );
  if( t==TK_ID 
   || t==TK_STRING 
   || t==TK_JOIN_KW 
   || t==TK_WINDOW 
   || t==TK_OVER 
   || sqlite3ParserFallback(t)==TK_ID 
  ){
    t = TK_ID;
  }
  *pz = z;
  return t;
}

/*
** The following three functions are called immediately after the tokenizer
** reads the keywords WINDOW, OVER and FILTER, respectively, to determine
** whether the token should be treated as a keyword or an SQL identifier.
** This cannot be handled by the usual lemon %fallback method, due to
** the ambiguity in some constructions. e.g.
**
**   SELECT sum(x) OVER ...
**
** In the above, "OVER" might be a keyword, or it might be an alias for the 
** sum(x) expression. If a "%fallback ID OVER" directive were added to 
** grammar, then SQLite would always treat "OVER" as an alias, making it
** impossible to call a window-function without a FILTER clause.
**
** WINDOW is treated as a keyword if:
**
**   * the following token is an identifier, or a keyword that can fallback
**     to being an identifier, and
**   * the token after than one is TK_AS.
**
** OVER is a keyword if:
**
**   * the previous token was TK_RP, and
**   * the next token is either TK_LP or an identifier.
**
** FILTER is a keyword if:
**
**   * the previous token was TK_RP, and
**   * the next token is TK_LP.
*/
static int analyzeWindowKeyword(const unsigned char *z){
  int t;
  t = getToken(&z);
  if( t!=TK_ID ) return TK_ID;
  t = getToken(&z);
  if( t!=TK_AS ) return TK_ID;
  return TK_WINDOW;
}
static int analyzeOverKeyword(const unsigned char *z, int lastToken){
  if( lastToken==TK_RP ){
    int t = getToken(&z);
    if( t==TK_LP || t==TK_ID ) return TK_OVER;
  }
  return TK_ID;
}
static int analyzeFilterKeyword(const unsigned char *z, int lastToken){
  if( lastToken==TK_RP && getToken(&z)==TK_LP ){
    return TK_FILTER;
  }
  return TK_ID;
}
#endif // SQLITE_OMIT_WINDOWFUNC

/*
** Return the length (in bytes) of the token that begins at z[0]. 
** Store the token type in *tokenType before returning.
*/
int sqlite3GetToken(const unsigned char *z, int *tokenType){
  int i, c;

  }
#endif
  assert( pParse->pNewTable==0 );
  assert( pParse->pNewTrigger==0 );
  assert( pParse->nVar==0 );
  assert( pParse->pVList==0 );
  while( 1 ){

    n = sqlite3GetToken((u8*)zSql, &tokenType);
    mxSqlLen -= n;
    if( mxSqlLen<0 ){
      pParse->rc = SQLITE_TOOBIG;
      break;
    }


#ifndef SQLITE_OMIT_WINDOWFUNC
    if( tokenType>=TK_WINDOW ){
      assert( tokenType==TK_SPACE || tokenType==TK_OVER || tokenType==TK_FILTER
           || tokenType==TK_ILLEGAL || tokenType==TK_WINDOW 


      );
#else




    if( tokenType>=TK_SPACE ){
      assert( tokenType==TK_SPACE || tokenType==TK_ILLEGAL );
#endif // SQLITE_OMIT_WINDOWFUNC
      if( db->u1.isInterrupted ){
        pParse->rc = SQLITE_INTERRUPT;
        break;
      }
      if( tokenType==TK_SPACE ){
        zSql += n;
        continue;
      }
      if( zSql[0]==0 ){
        /* Upon reaching the end of input, call the parser two more times
        ** with tokens TK_SEMI and 0, in that order. */
        if( lastTokenParsed==TK_SEMI ){
          tokenType = 0;
        }else if( lastTokenParsed==0 ){
          break;
        }else{
          tokenType = TK_SEMI;
        }
        n = 0;
#ifndef SQLITE_OMIT_WINDOWFUNC
      }else if( tokenType==TK_WINDOW ){
        assert( n==6 );
        tokenType = analyzeWindowKeyword((const u8*)&zSql[6]);
      }else if( tokenType==TK_OVER ){
        assert( n==4 );
        tokenType = analyzeOverKeyword((const u8*)&zSql[4], lastTokenParsed);
      }else if( tokenType==TK_FILTER ){
        assert( n==6 );
        tokenType = analyzeFilterKeyword((const u8*)&zSql[6], lastTokenParsed);
#endif // SQLITE_OMIT_WINDOWFUNC
      }else{
        sqlite3ErrorMsg(pParse, "unrecognized token: \"%.*s\"", n, zSql);
        break;
      }
    }
    pParse->sLastToken.z = zSql;
    pParse->sLastToken.n = n;
    sqlite3Parser(pEngine, tokenType, pParse->sLastToken);
    lastTokenParsed = tokenType;
    zSql += n;
    if( pParse->rc!=SQLITE_OK || db->mallocFailed ) break;

  }
  assert( nErr==0 );
#ifdef YYTRACKMAXSTACKDEPTH
  sqlite3_mutex_enter(sqlite3MallocMutex());
  sqlite3StatusHighwater(SQLITE_STATUS_PARSER_STACK,
      sqlite3ParserStackPeak(pEngine)
  );

# 2018 May 8
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library. Specifically,
# it tests the sqlite3_create_window_function() API.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix window6

ifcapable !windowfunc {
  finish_test
  return
}

set setup {
  CREATE TABLE %t1(%x, %y %typename);
  INSERT INTO %t1 VALUES(1, 'a');
  INSERT INTO %t1 VALUES(2, 'b');
  INSERT INTO %t1 VALUES(3, 'c');
  INSERT INTO %t1 VALUES(4, 'd');
  INSERT INTO %t1 VALUES(5, 'e');
}

foreach {tn vars} {
  1 {}
  2 { set A(%t1) over }
  3 { set A(%x)  over }
  4 { 
    set A(%alias)   over 
    set A(%x)       following 
    set A(%y)       over 
  }
  5 { 
    set A(%t1)      over
    set A(%x)       following 
    set A(%y)       preceding 
    set A(%w)       current 
    set A(%alias)   filter
    set A(%typename)  window
  }

  6 { 
    set A(%x)       window 
  }
} {
  set A(%t1)    t1
  set A(%x)     x
  set A(%y)     y
  set A(%w)     w
  set A(%alias) alias
  set A(%typename) integer
  eval $vars

  set MAP [array get A]
  set setup_sql [string map $MAP $setup]
  reset_db
  execsql $setup_sql

  do_execsql_test 1.$tn.1 [string map $MAP {
    SELECT group_concat(%x, '.') OVER (ORDER BY %y) FROM %t1
  }] {1 1.2 1.2.3 1.2.3.4 1.2.3.4.5}

  do_execsql_test 1.$tn.2 [string map $MAP {
    SELECT sum(%x) OVER %w FROM %t1 WINDOW %w AS (ORDER BY %y)
  }] {1 3 6 10 15}

  do_execsql_test 1.$tn.3 [string map $MAP {
    SELECT sum(%alias.%x) OVER %w FROM %t1 %alias WINDOW %w AS (ORDER BY %y)
  }] {1 3 6 10 15}

  do_execsql_test 1.$tn.4 [string map $MAP {
    SELECT sum(%x) %alias FROM %t1
  }] {15}
}


proc winproc {args} { return "window: $args" }
db func window winproc
do_execsql_test 2.0 {
  SELECT window('hello world');
} {{window: {hello world}}}

proc wincmp {a b} { string compare $b $a }
db collate window wincmp
do_execsql_test 3.0 {
  CREATE TABLE window(x COLLATE window);
  INSERT INTO window VALUES('bob'), ('alice'), ('cate');
  SELECT * FROM window ORDER BY x COLLATE window;
} {cate bob alice}
do_execsql_test 3.1 {
  DROP TABLE window;
  CREATE TABLE x1(x);
  INSERT INTO x1 VALUES('bob'), ('alice'), ('cate');
  CREATE INDEX window ON x1(x COLLATE window);
  SELECT * FROM x1 ORDER BY x COLLATE window;
} {cate bob alice}


do_execsql_test 4.0 { CREATE TABLE t4(x, y); }

# do_execsql_test 4.1 { PRAGMA parser_trace = 1 }
do_execsql_test 4.1 { 
  SELECT * FROM t4 window, t4;
}

#-------------------------------------------------------------------------
reset_db

do_execsql_test 5.0 {
  CREATE TABLE over(x, over);
  CREATE TABLE window(x, window);
  INSERT INTO over VALUES(1, 2), (3, 4), (5, 6);
  INSERT INTO window VALUES(1, 2), (3, 4), (5, 6);
  SELECT sum(x) over FROM over
} {9}

do_execsql_test 5.1 {
  SELECT sum(x) over over FROM over WINDOW over AS ()
} {9 9 9}

do_execsql_test 5.2 {
  SELECT sum(over) over over over FROM over over WINDOW over AS (ORDER BY over)
} {2 6 12}

do_execsql_test 5.3 {
  SELECT sum(over) over over over FROM over over WINDOW over AS (ORDER BY over);
} {2 6 12}

do_execsql_test 5.4 {
  SELECT sum(window) OVER window window FROM window window window window AS (ORDER BY window);
} {2 6 12}

finish_test

*/
#ifndef INTERFACE
# define INTERFACE 1
#endif
/************* Begin control #defines *****************************************/
%%
/************* End control #defines *******************************************/
#define YY_NLOOKAHEAD ((int)(sizeof(yy_lookahead)/sizeof(yy_lookahead[0])))

/* Define the yytestcase() macro to be a no-op if is not already defined
** otherwise.
**
** Applications can choose to define yytestcase() in the %include section
** to a macro that can assist in verifying code coverage.  For production
** code the yytestcase() macro should be turned off.  But it is useful

  assert( stateno <= YY_SHIFT_COUNT );
#if defined(YYCOVERAGE)
  yycoverage[stateno][iLookAhead] = 1;
#endif
  do{
    i = yy_shift_ofst[stateno];
    assert( i>=0 );
    /* assert( i+YYNTOKEN<=(int)YY_NLOOKAHEAD ); */
    assert( iLookAhead!=YYNOCODE );
    assert( iLookAhead < YYNTOKEN );
    i += iLookAhead;
    if( i>=YY_NLOOKAHEAD || yy_lookahead[i]!=iLookAhead ){
#ifdef YYFALLBACK
      YYCODETYPE iFallback;            /* Fallback token */
      if( iLookAhead<sizeof(yyFallback)/sizeof(yyFallback[0])
             && (iFallback = yyFallback[iLookAhead])!=0 ){
#ifndef NDEBUG
        if( yyTraceFILE ){
          fprintf(yyTraceFILE, "%sFALLBACK %s => %s\n",

      cDiv = ' ';
    }
    fprintf(yyTraceFILE,"]\n");
  }
#endif
  return;
}

/*
** Return the fallback token corresponding to canonical token iToken, or
** 0 if iToken has no fallback.
*/
int ParseFallback(int iToken){
#ifdef YYFALLBACK
  if( iToken<sizeof(yyFallback)/sizeof(yyFallback[0]) ){
    return yyFallback[iToken];
  }
#endif
  return 0;
}