SQLite

  INSERT INTO rt0(a,b,c) VALUES(0,0.0,0.0);
  CREATE VIEW v0(x) AS SELECT DISTINCT rt0.b FROM rt0;
  SELECT v0.x FROM v0, rt0;
} {0.0}
do_execsql_test 19.1 {
  SELECT v0.x FROM v0, rt0 WHERE v0.x = rt0.b;
} {0.0}

# 2022-06-20 https://sqlite.org/forum/forumpost/57bdf2217d
#
reset_db
do_execsql_test 20.0 {
  CREATE VIRTUAL TABLE rt0 USING rtree(id, x0, x1);
  CREATE TABLE t0(a INT);
  CREATE TABLE t1(b INT);
  INSERT INTO rt0 VALUES(0, 0, 0);
  SELECT * FROM t1 JOIN t0 ON x0>a RIGHT JOIN rt0 ON true WHERE +x0 = 0;
} {}
do_execsql_test 20.1 {
  SELECT * FROM t1 JOIN t0 ON x0>a RIGHT JOIN rt0 ON true WHERE x0 = 0;
} {}

finish_test

typedef struct WhereConst WhereConst;
struct WhereConst {
  Parse *pParse;   /* Parsing context */
  u8 *pOomFault;   /* Pointer to pParse->db->mallocFailed */
  int nConst;      /* Number for COLUMN=CONSTANT terms */
  int nChng;       /* Number of times a constant is propagated */
  int bHasAffBlob; /* At least one column in apExpr[] as affinity BLOB */
  u32 mExcludeOn;  /* Which ON expressions to exclude from considertion.
                   ** Either EP_OuterON or EP_InnerON|EP_OuterON */
  Expr **apExpr;   /* [i*2] is COLUMN and [i*2+1] is VALUE */
};

/*
** Add a new entry to the pConst object.  Except, do not add duplicate
** pColumn entires.  Also, do not add if doing so would not be appropriate.
**

** is a constant expression and where the term must be true because it
** is part of the AND-connected terms of the expression.  For each term
** found, add it to the pConst structure.
*/
static void findConstInWhere(WhereConst *pConst, Expr *pExpr){
  Expr *pRight, *pLeft;
  if( NEVER(pExpr==0) ) return;
  if( ExprHasProperty(pExpr, pConst->mExcludeOn) ){
    testcase( ExprHasProperty(pExpr, EP_OuterON) );
    testcase( ExprHasProperty(pExpr, EP_InnerON) );
    return;
  }
  if( pExpr->op==TK_AND ){
    findConstInWhere(pConst, pExpr->pRight);
    findConstInWhere(pConst, pExpr->pLeft);

  WhereConst *pConst,
  Expr *pExpr, 
  int bIgnoreAffBlob
){
  int i;
  if( pConst->pOomFault[0] ) return WRC_Prune;
  if( pExpr->op!=TK_COLUMN ) return WRC_Continue;
  if( ExprHasProperty(pExpr, EP_FixedCol|pConst->mExcludeOn) ){
    testcase( ExprHasProperty(pExpr, EP_FixedCol) );
    testcase( ExprHasProperty(pExpr, EP_OuterON) );
    testcase( ExprHasProperty(pExpr, EP_InnerON) );
    return WRC_Continue;
  }
  for(i=0; i<pConst->nConst; i++){
    Expr *pColumn = pConst->apExpr[i*2];
    if( pColumn==pExpr ) continue;
    if( pColumn->iTable!=pExpr->iTable ) continue;
    if( pColumn->iColumn!=pExpr->iColumn ) continue;

  x.pParse = pParse;
  x.pOomFault = &pParse->db->mallocFailed;
  do{
    x.nConst = 0;
    x.nChng = 0;
    x.apExpr = 0;
    x.bHasAffBlob = 0;
    if( ALWAYS(p->pSrc!=0)
     && p->pSrc->nSrc>0
     && (p->pSrc->a[0].fg.jointype & JT_LTORJ)!=0
    ){
      /* Do not propagate constants on any ON clause if there is a
      ** RIGHT JOIN anywhere in the query */
      x.mExcludeOn = EP_InnerON | EP_OuterON;
    }else{
      /* Do not propagate constants through the ON clause of a LEFT JOIN */
      x.mExcludeOn = EP_OuterON;
    }
    findConstInWhere(&x, p->pWhere);
    if( x.nConst ){
      memset(&w, 0, sizeof(w));
      w.pParse = pParse;
      w.xExprCallback = propagateConstantExprRewrite;
      w.xSelectCallback = sqlite3SelectWalkNoop;
      w.xSelectCallback2 = 0;

    FROM (SELECT 99 as "m" FROM t2 JOIN v0 ON z<>'' RIGHT JOIN t1 ON z<>'' ORDER BY z) AS "t3";
} {1}

# 2022-06-10
# https://sqlite.org/forum/forumpost/8e4c352937e82929
#
# Do not allow constant propagation between ON and WHERE clause terms.
# (Updated 2022-06-20) See also https://sqlite.org/forum/forumpost/57bdf2217d
#
reset_db
do_execsql_test join8-21000 {
  CREATE TABLE t1(a INT,b BOOLEAN);
  CREATE TABLE t2(c INT);  INSERT INTO t2 VALUES(NULL);
  CREATE TABLE t3(d INT);
}
do_execsql_test join8-21010 {
  SELECT (b IS TRUE) FROM t1 JOIN t3 ON (b=TRUE) RIGHT JOIN t2 ON TRUE;
} {0}
do_execsql_test join8-22020 {
  SELECT * FROM t1 JOIN t3 ON (b=TRUE) RIGHT JOIN t2 ON TRUE WHERE (b IS TRUE);
} {}
do_execsql_test join8-22030 {
  DROP TABLE t1;
  DROP TABLE t2;
  DROP TABLE t3;
  CREATE TABLE t1(a INT);
  CREATE TABLE t2(b INT);
  CREATE TABLE t3(c INTEGER PRIMARY KEY, d INT);
  CREATE INDEX t3d ON t3(d);
  INSERT INTO t3 VALUES(0, 0);
  SELECT * FROM t1 JOIN t2 ON d>b RIGHT JOIN t3 ON true WHERE +d = 0;
} {}
do_execsql_test join8-22040 {
  SELECT * FROM t1 JOIN t2 ON d>b RIGHT JOIN t3 ON true WHERE d = 0;
} {}


# 2022-06-10
# https://sqlite.org/forum/forumpost/51e6959f61
#
# Restrictions on the usage of WHERE clause constraints by joins that are
# involved with a RIGHT JOIN must also be applied to automatic indexes.
#