93   if( !sqlite3BtreeSharable(pParse->db->aDb[iDb].pBt) ) return;  in sqlite3TableLock()
617     if( pDb->pBt==0 ){  in sqlite3CollapseDatabaseArray()
1918    && !sqlite3BtreeIsReadonly(db->aDb[db->init.iDb].pBt)  in sqlite3AddCheckConstraint()
5127       Btree *pBt = db->aDb[i].pBt;  in sqlite3BeginTransaction()  local
5128       if( pBt && sqlite3BtreeIsReadonly(pBt) ){  in sqlite3BeginTransaction()
5191   if( db->aDb[1].pBt==0 && !pParse->explain ){  in sqlite3OpenTempDatabase()
5193     Btree *pBt;  in sqlite3OpenTempDatabase()  local
5201     rc = sqlite3BtreeOpen(db->pVfs, 0, db, &pBt, 0, flags);  in sqlite3OpenTempDatabase()
5208     db->aDb[1].pBt = pBt;  in sqlite3OpenTempDatabase()
5210     if( SQLITE_NOMEM==sqlite3BtreeSetPageSize(pBt, db->nextPagesize, 0, 0) ){  in sqlite3OpenTempDatabase()
5226   assert( pToplevel->db->aDb[iDb].pBt!=0 || iDb==1 );  in sqlite3CodeVerifySchemaAtToplevel()
5250     if( pDb->pBt && (!zDb || 0==sqlite3StrICmp(zDb, pDb->zDbSName)) ){  in sqlite3CodeVerifyNamedSchema()