8 { INSERT INTO t2 VALUES(1, 2, 3) }       { {INSERT t2 {} {i 1 i 2 i 3}} }
  9 { DELETE FROM t2 WHERE 1 }               { {DELETE t2 {i 1 i 2 i 3} {}} }

} {
  do_iterator_test 4.$tn {t1 t2 t3} $sql $changeset
}


























finish_test

  8 { INSERT INTO t2 VALUES(1, 2, 3) }       { {INSERT t2 {} {i 1 i 2 i 3}} }
  9 { DELETE FROM t2 WHERE 1 }               { {DELETE t2 {i 1 i 2 i 3} {}} }

} {
  do_iterator_test 4.$tn {t1 t2 t3} $sql $changeset
}


#-------------------------------------------------------------------------
# Test that if NULL is passed to sqlite3session_attach(), all database
# tables are attached to the session object.
#
test_reset
do_execsql_test 5.0 {
  CREATE TABLE t1(a PRIMARY KEY);
  CREATE TABLE t2(x, y PRIMARY KEY);
}

foreach {tn sql changeset} {
  1 { INSERT INTO t1 VALUES(35) }     { {INSERT t1 {} {i 35}} }
  2 { INSERT INTO t2 VALUES(36, 37) } { {INSERT t2 {} {i 36 i 37}} }
  3 { 
    DELETE FROM t1 WHERE 1;
    UPDATE t2 SET x = 34;
  } { 
    {UPDATE t2 {i 36 i 37} {i 34 {} {}}}
    {DELETE t1 {i 35} {}}
  }
} {
  do_iterator_test 5.$tn * $sql $changeset
}

finish_test

  catch { S delete }

  if {$rc} {error $msg}
}

proc do_iterator_test {tn tbl_list sql res} {
  sqlite3session S db main

  foreach t $tbl_list {S attach $t}

  execsql $sql

  set r [list]
  foreach v $res { lappend r $v }

  set x [list]
  sqlite3session_foreach c [S changeset] { lappend x $c }

  catch { S delete }

  if {$rc} {error $msg}
}

proc do_iterator_test {tn tbl_list sql res} {
  sqlite3session S db main
  if {[llength $tbl_list]==0} { S attach * }
  foreach t $tbl_list {S attach $t}

  execsql $sql

  set r [list]
  foreach v $res { lappend r $v }

  set x [list]
  sqlite3session_foreach c [S changeset] { lappend x $c }

/*
** Session handle structure.
*/
struct sqlite3_session {
  sqlite3 *db;                    /* Database handle session is attached to */
  char *zDb;                      /* Name of database session is attached to */
  int bEnable;                    /* True if currently recording */

  int rc;                         /* Non-zero if an error has occurred */
  sqlite3_session *pNext;         /* Next session object on same db. */
  SessionTable *pTable;           /* List of attached tables */
};

/*
** Structure for changeset iterators.
................................................................................
    /* If this session is attached to a different database ("main", "temp" 
    ** etc.), or if it is not currently enabled, there is nothing to do. Skip 
    ** to the next session object attached to this database. */
    if( pSession->bEnable==0 ) continue;
    if( pSession->rc ) continue;
    if( sqlite3_strnicmp(zDb, pSession->zDb, nDb+1) ) continue;

    for(pTab=pSession->pTable; pTab; pTab=pTab->pNext){









      if( 0==sqlite3_strnicmp(pTab->zName, zName, nName+1) ){
        sessionPreupdateOneChange(op, pSession, pTab);
        if( op==SQLITE_UPDATE ){
          sessionPreupdateOneChange(SQLITE_INSERT, pSession, pTab);
        }
        break;
      }
................................................................................
** not matter if the PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias)
** or not.
*/
int sqlite3session_attach(
  sqlite3_session *pSession,      /* Session object */
  const char *zName               /* Table name */
){
  SessionTable *pTab;             /* New table object (if required) */
  int nName;                      /* Number of bytes in string zName */
  int rc = SQLITE_OK;



  sqlite3_mutex_enter(sqlite3_db_mutex(pSession->db));




  /* First search for an existing entry. If one is found, this call is
  ** a no-op. Return early. */
  nName = strlen(zName);
  for(pTab=pSession->pTable; pTab; pTab=pTab->pNext){
    if( 0==sqlite3_strnicmp(pTab->zName, zName, nName+1) ) break;
  }

  if( !pTab ){
    /* Allocate new SessionTable object. */
    pTab = (SessionTable *)sqlite3_malloc(sizeof(SessionTable) + nName + 1);
    if( !pTab ){
      rc = SQLITE_NOMEM;
    }else{
      /* Populate the new SessionTable object and link it into the list. */
      memset(pTab, 0, sizeof(SessionTable));
      pTab->zName = (char *)&pTab[1];
      memcpy(pTab->zName, zName, nName+1);
      pTab->pNext = pSession->pTable;
      pSession->pTable = pTab;

    }
  }

  sqlite3_mutex_leave(sqlite3_db_mutex(pSession->db));
  return rc;
}

/*
** Session handle structure.
*/
struct sqlite3_session {
  sqlite3 *db;                    /* Database handle session is attached to */
  char *zDb;                      /* Name of database session is attached to */
  int bEnable;                    /* True if currently recording */
  int bAutoAttach;                /* True to auto-attach tables */
  int rc;                         /* Non-zero if an error has occurred */
  sqlite3_session *pNext;         /* Next session object on same db. */
  SessionTable *pTable;           /* List of attached tables */
};

/*
** Structure for changeset iterators.
................................................................................
    /* If this session is attached to a different database ("main", "temp" 
    ** etc.), or if it is not currently enabled, there is nothing to do. Skip 
    ** to the next session object attached to this database. */
    if( pSession->bEnable==0 ) continue;
    if( pSession->rc ) continue;
    if( sqlite3_strnicmp(zDb, pSession->zDb, nDb+1) ) continue;

    for(pTab=pSession->pTable; pTab || pSession->bAutoAttach; pTab=pTab->pNext){
      if( !pTab ){
        /* This branch is taken if table zName has not yet been attached to
        ** this session and the auto-attach flag is set.  */
        pSession->rc = sqlite3session_attach(pSession,zName);
        if( pSession->rc ) continue;
        pTab = pSession->pTable;
        assert( 0==sqlite3_strnicmp(pTab->zName, zName, nName+1) );
      }

      if( 0==sqlite3_strnicmp(pTab->zName, zName, nName+1) ){
        sessionPreupdateOneChange(op, pSession, pTab);
        if( op==SQLITE_UPDATE ){
          sessionPreupdateOneChange(SQLITE_INSERT, pSession, pTab);
        }
        break;
      }
................................................................................
** not matter if the PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias)
** or not.
*/
int sqlite3session_attach(
  sqlite3_session *pSession,      /* Session object */
  const char *zName               /* Table name */
){


  int rc = SQLITE_OK;
  sqlite3_mutex_enter(sqlite3_db_mutex(pSession->db));

  if( !zName ){
    pSession->bAutoAttach = 1;
  }else{
    SessionTable *pTab;           /* New table object (if required) */
    int nName;                    /* Number of bytes in string zName */

    /* First search for an existing entry. If one is found, this call is
    ** a no-op. Return early. */
    nName = strlen(zName);
    for(pTab=pSession->pTable; pTab; pTab=pTab->pNext){
      if( 0==sqlite3_strnicmp(pTab->zName, zName, nName+1) ) break;
    }

    if( !pTab ){
      /* Allocate new SessionTable object. */
      pTab = (SessionTable *)sqlite3_malloc(sizeof(SessionTable) + nName + 1);
      if( !pTab ){
        rc = SQLITE_NOMEM;
      }else{
        /* Populate the new SessionTable object and link it into the list. */
        memset(pTab, 0, sizeof(SessionTable));
        pTab->zName = (char *)&pTab[1];
        memcpy(pTab->zName, zName, nName+1);
        pTab->pNext = pSession->pTable;
        pSession->pTable = pTab;
      }
    }
  }

  sqlite3_mutex_leave(sqlite3_db_mutex(pSession->db));
  return rc;
}

** the session is disabled, or 1 if it is enabled.
*/
int sqlite3session_enable(sqlite3_session *pSession, int bEnable);

/*
** CAPI3REF: Attach A Table To A Session Object
**
** Attach a table to a session. All subsequent changes made to the table

** while the session object is enabled will be recorded. See documentation
** for [sqlite3session_changeset()] for further details.





**
** Changes can only be recorded for tables that have a PRIMARY KEY explicitly
** defined as part of their CREATE TABLE statement. It does not matter if the 
** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY
** KEY may consist of a single column, or may be a composite key.
** 
** It is not an error if the named table does not exist in the database. Nor
** is it an error if the named table does not have a PRIMARY KEY. However,
** no changes will be recorded in either of these scenarios.
**
** Changes are not recorded for individual rows that have NULL values stored
** in one or more of their PRIMARY KEY columns.
**
** SQLITE_OK is returned if the table is successfully attached to the session
** object. Or, if an error occurs, an SQLite error code (e.g. SQLITE_NOMEM)
** is returned.
*/
int sqlite3session_attach(
  sqlite3_session *pSession,      /* Session object */
  const char *zTab                /* Table name */
);

/*

** the session is disabled, or 1 if it is enabled.
*/
int sqlite3session_enable(sqlite3_session *pSession, int bEnable);

/*
** CAPI3REF: Attach A Table To A Session Object
**
** If argument zTab is not NULL, then it is the name of a table to attach
** to the session object passed as the first argument. All subsequent changes 
** made to the table while the session object is enabled will be recorded. See 
** documentation for [sqlite3session_changeset()] for further details.
**
** Or, if argument zTab is NULL, then changes are recorded for all tables
** in the database. If additional tables are added to the database (by 
** executing "CREATE TABLE" statements) after this call is made, changes for 
** the new tables are also recorded.
**
** Changes can only be recorded for tables that have a PRIMARY KEY explicitly
** defined as part of their CREATE TABLE statement. It does not matter if the 
** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY
** KEY may consist of a single column, or may be a composite key.
** 
** It is not an error if the named table does not exist in the database. Nor
** is it an error if the named table does not have a PRIMARY KEY. However,
** no changes will be recorded in either of these scenarios.
**
** Changes are not recorded for individual rows that have NULL values stored
** in one or more of their PRIMARY KEY columns.
**
** SQLITE_OK is returned if the call completes without error. Or, if an error 
** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned.

*/
int sqlite3session_attach(
  sqlite3_session *pSession,      /* Session object */
  const char *zTab                /* Table name */
);

/*

  if( rc!=TCL_OK ) return rc;
  if( objc!=2+aSub[iSub].nArg ){
    Tcl_WrongNumArgs(interp, 2, objv, aSub[iSub].zMsg);
    return TCL_ERROR;
  }

  switch( iSub ){
    case 0:        /* attach */


      rc = sqlite3session_attach(pSession, Tcl_GetString(objv[2]));
      if( rc!=SQLITE_OK ){
        return test_session_error(interp, rc);
      }

      break;

    case 1: {      /* changeset */
      int nChange;
      void *pChange;
      rc = sqlite3session_changeset(pSession, &nChange, &pChange);
      if( rc==SQLITE_OK ){

  if( rc!=TCL_OK ) return rc;
  if( objc!=2+aSub[iSub].nArg ){
    Tcl_WrongNumArgs(interp, 2, objv, aSub[iSub].zMsg);
    return TCL_ERROR;
  }

  switch( iSub ){
    case 0: {      /* attach */
      char *zArg = Tcl_GetString(objv[2]);
      if( zArg[0]=='*' && zArg[1]=='\0' ) zArg = 0;
      rc = sqlite3session_attach(pSession, zArg);
      if( rc!=SQLITE_OK ){
        return test_session_error(interp, rc);
      }
    }
      break;

    case 1: {      /* changeset */
      int nChange;
      void *pChange;
      rc = sqlite3session_changeset(pSession, &nChange, &pChange);
      if( rc==SQLITE_OK ){