SQLite

    }
    if( sqlite3FixExpr(pFix, pStep->pWhere) ){
      return 1;
    }
    if( sqlite3FixExprList(pFix, pStep->pExprList) ){
      return 1;
    }
#ifndef SQLITE_OMIT_UPSERT
    if( pStep->pUpsert ){
      Upsert *pUp = pStep->pUpsert;
      if( sqlite3FixExprList(pFix, pUp->pUpsertTarget)
       || sqlite3FixExpr(pFix, pUp->pUpsertTargetWhere)
       || sqlite3FixExprList(pFix, pUp->pUpsertSet)
       || sqlite3FixExpr(pFix, pUp->pUpsertWhere)
      ){
        return 1;
      }
    }
#endif
    pStep = pStep->pNext;
  }
  return 0;
}
#endif

** The pUpsertSet field is NULL for a ON CONFLICT DO NOTHING.  The
** pUpsertWhere is the WHERE clause for the UPDATE and is NULL if the
** WHERE clause is omitted.
*/
struct Upsert {
  ExprList *pUpsertTarget;  /* Optional description of conflicting index */
  Expr *pUpsertTargetWhere; /* WHERE clause for partial index targets */
  Index *pUpsertIdx;        /* Constraint that pUpsertTarget identifies */
  ExprList *pUpsertSet;     /* The SET clause from an ON CONFLICT UPDATE */
  Expr *pUpsertWhere;       /* WHERE clause for the ON CONFLICT UPDATE */
  /* The fields above comprise the parse tree for the upsert clause.
  ** The fields below are used to transfer information from the INSERT
  ** processing down into the UPDATE processing while generating code.
  ** Upsert owns the memory allocated above, but not the memory below. */
  Index *pUpsertIdx;        /* Constraint that pUpsertTarget identifies */
  SrcList *pUpsertSrc;      /* Table to be updated */
  int regData;              /* First register holding array of VALUES */
  int iDataCur;             /* Index of the data cursor */
  int iIdxCur;              /* Index of the first index cursor */
};

/*