SQLite

  int maxStmt;               /* The next maximum number of stmtList */
  int nStmt;                 /* Number of statements in stmtList */
  IncrblobChannel *pIncrblob;/* Linked list of open incrblob channels */
  int nStep, nSort, nIndex;  /* Statistics for most recent operation */
  int nVMStep;               /* Another statistic for most recent operation */
  int nTransaction;          /* Number of nested [transaction] methods */
  int openFlags;             /* Flags used to open.  (SQLITE_OPEN_URI) */
  int nRef;                  /* Delete object when this reaches 0 */
#ifdef SQLITE_TEST
  int bLegacyPrepare;        /* True to use sqlite3_prepare() */
#endif
};

struct IncrblobChannel {
  sqlite3_blob *pBlob;      /* sqlite3 blob handle */

    pNext = pPreStmt->pNext;
    dbFreeStmt(pPreStmt);
  }
  pDb->nStmt = 0;
  pDb->stmtLast = 0;
  pDb->stmtList = 0;
}

/*
** Increment the reference counter on the SqliteDb object. The reference
** should be released by calling delDatabaseRef().
*/
static void addDatabaseRef(SqliteDb *pDb){
  pDb->nRef++;
}

/*
** Decrement the reference counter associated with the SqliteDb object.
** If it reaches zero, delete the object.
*/
static void delDatabaseRef(SqliteDb *pDb){
  assert( pDb->nRef>0 );
  pDb->nRef--;
  if( pDb->nRef==0 ){
    flushStmtCache(pDb);
    closeIncrblobChannels(pDb);
    sqlite3_close(pDb->db);
    while( pDb->pFunc ){
      SqlFunc *pFunc = pDb->pFunc;
      pDb->pFunc = pFunc->pNext;
      assert( pFunc->pDb==pDb );
      Tcl_DecrRefCount(pFunc->pScript);
      Tcl_Free((char*)pFunc);
    }
    while( pDb->pCollate ){
      SqlCollate *pCollate = pDb->pCollate;
      pDb->pCollate = pCollate->pNext;
      Tcl_Free((char*)pCollate);
    }
    if( pDb->zBusy ){
      Tcl_Free(pDb->zBusy);
    }
    if( pDb->zTrace ){
      Tcl_Free(pDb->zTrace);
    }
    if( pDb->zTraceV2 ){
      Tcl_Free(pDb->zTraceV2);
    }
    if( pDb->zProfile ){
      Tcl_Free(pDb->zProfile);
    }
    if( pDb->zBindFallback ){
      Tcl_Free(pDb->zBindFallback);
    }
    if( pDb->zAuth ){
      Tcl_Free(pDb->zAuth);
    }
    if( pDb->zNull ){
      Tcl_Free(pDb->zNull);
    }
    if( pDb->pUpdateHook ){
      Tcl_DecrRefCount(pDb->pUpdateHook);
    }
    if( pDb->pPreUpdateHook ){
      Tcl_DecrRefCount(pDb->pPreUpdateHook);
    }
    if( pDb->pRollbackHook ){
      Tcl_DecrRefCount(pDb->pRollbackHook);
    }
    if( pDb->pWalHook ){
      Tcl_DecrRefCount(pDb->pWalHook);
    }
    if( pDb->pCollateNeeded ){
      Tcl_DecrRefCount(pDb->pCollateNeeded);
    }
    Tcl_Free((char*)pDb);
  }
}

/*
** TCL calls this procedure when an sqlite3 database command is
** deleted.
*/
static void SQLITE_TCLAPI DbDeleteCmd(void *db){
  SqliteDb *pDb = (SqliteDb*)db;
  delDatabaseRef(pDb);



















































}

/*
** This routine is called when a database file is locked while trying
** to execute SQL.
*/
static int DbBusyHandler(void *cd, int nTries){

      Tcl_AppendResult(interp, sqlite3_errmsg(pDb->db), (char*)0);
      rc = TCL_ERROR;
    }
    sqlite3_exec(pDb->db, "ROLLBACK", 0, 0, 0);
  }
  pDb->disableAuth--;

  delDatabaseRef(pDb);
  return rc;
}

/*
** Unless SQLITE_TEST is defined, this function is a simple wrapper around
** sqlite3_prepare_v2(). If SQLITE_TEST is defined, then it uses either
** sqlite3_prepare_v2() or legacy interface sqlite3_prepare(), depending

  p->pSql = pSql;
  Tcl_IncrRefCount(pSql);
  if( pArray ){
    p->pArray = pArray;
    Tcl_IncrRefCount(pArray);
  }
  p->evalFlags = evalFlags;
  addDatabaseRef(p->pDb);
}

/*
** Obtain information about the row that the DbEvalContext passed as the
** first argument currently points to.
*/
static void dbEvalRowInfo(

  }
  if( p->pArray ){
    Tcl_DecrRefCount(p->pArray);
    p->pArray = 0;
  }
  Tcl_DecrRefCount(p->pSql);
  dbReleaseColumnNames(p);
  delDatabaseRef(p->pDb);
}

/*
** Return a pointer to a Tcl_Obj structure with ref-count 0 that contains
** the value for the iCol'th column of the row currently pointed to by
** the DbEvalContext structure passed as the first argument.
*/

    pDb->nTransaction++;

    /* If using NRE, schedule a callback to invoke the script pScript, then
    ** a second callback to commit (or rollback) the transaction or savepoint
    ** opened above. If not using NRE, evaluate the script directly, then
    ** call function DbTransPostCmd() to commit (or rollback) the transaction
    ** or savepoint.  */
    addDatabaseRef(pDb);          /* DbTransPostCmd() calls delDatabaseRef() */
    if( DbUseNre() ){
      Tcl_NRAddCallback(interp, DbTransPostCmd, cd, 0, 0, 0);
      (void)Tcl_NREvalObj(interp, pScript, 0);
    }else{
      rc = DbTransPostCmd(&cd, interp, Tcl_EvalObjEx(interp, pScript, 0));
    }
    break;

  zArg = Tcl_GetStringFromObj(objv[1], 0);
  if( DbUseNre() ){
    Tcl_NRCreateCommand(interp, zArg, DbObjCmdAdaptor, DbObjCmd,
                        (char*)p, DbDeleteCmd);
  }else{
    Tcl_CreateObjCommand(interp, zArg, DbObjCmd, (char*)p, DbDeleteCmd);
  }
  p->nRef = 1;
  return TCL_OK;
}

/*
** Provide a dummy Tcl_InitStubs if we are using this as a static
** library.
*/

  db bind_fallback bind_fallback_does_not_exist
} {}
do_catchsql_test 19.911 {
  SELECT $abc, typeof($abc), $def, typeof($def), $ghi, typeof($ghi);
} {1 {invalid command name "bind_fallback_does_not_exist"}}
db bind_fallback {}

#-------------------------------------------------------------------------
do_test 20.0 {
  db transaction {
    db close
  }
} {}

do_test 20.1 {
  sqlite3 db test.db
  set rc [catch {
    db eval {SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3} { db close }
  } msg]
  list $rc $msg
} {1 {invalid command name "db"}}
  

proc closedb {} {
  db close
  return 10
}
proc func1 {} { return 1 }

sqlite3 db test.db
db func closedb closedb
db func func1 func1

do_test 20.2 {
  set rc [catch {
    db eval {
      SELECT closedb(),func1() UNION ALL SELECT 20,30 UNION ALL SELECT 30,40
    }
  } msg]
  list $rc $msg
} {0 {10 1 20 30 30 40}}

finish_test