|
![]() ![]()
|
Access method operations
Once a database handle has been created using db_create, there are several standard access method operations. Each of these operations is performed using a method referred to by the returned handle. Generally, the database will be opened using DB->open. If the database is from an old release of Berkeley DB, it may need to be upgraded to the current release before it is opened using DB->upgrade.
Once a database has been opened, records may be retrieved (DB->get), stored (DB->put), and deleted (DB->del).
Additional operations supported by the database handle include statistics (DB->stat), truncation (DB->truncate), version upgrade (DB->upgrade), verification and salvage (DB->verify), flushing to a backing file (DB->sync), and association of secondary indices (DB->associate). Database handles are eventually closed using DB->close.
| Database Operations | Description |
|---|---|
| db_create | Create a database handle |
| DB->associate | Associate a secondary index |
| DB->close | Close a database |
| DB->compact | Compact a database |
| DB->cursor | Create a cursor |
| DB->del | Delete items from a database |
| DB->err, DB->errx | Error message |
| DB->exists | Return if an item appears in a database |
| DB->fd | Return a file descriptor from a database |
| DB->get, DB->pget | Get items from a database |
| DB->get_byteswapped | Return if the underlying database is in host order |
| DB->get_type | Return the database type |
| DB->join | Perform a database join on cursors |
| DB->key_range | Return estimate of key location |
| DB->open | Open a database |
| DB->put | Store items into a database |
| DB->remove | Remove a database |
| DB->rename | Rename a database |
| DB->set_priority | Set cache page priority |
| DB->stat, DB->stat_print | Database statistics |
| DB->sync | Flush a database to stable storage |
| DB->truncate | Empty a database |
| DB->upgrade | Upgrade a database |
| DB->verify | Verify/salvage a database |
| Database Configuration | |
| DB->set_alloc | Set local space allocation functions |
| DB->set_cachesize | Set the database cache size |
| DB->set_dup_compare | Set a duplicate comparison function |
| DB->set_encrypt | Set the database cryptographic key |
| DB->set_errcall, DB->set_msgcall | Set error and informational message callback |
| DB->set_errfile, DB->set_msgfile | Set error and informational message FILE |
| DB->set_errpfx | Set error message prefix |
| DB->set_feedback | Set feedback callback |
| DB->set_flags | General database configuration |
| DB->set_lorder | Set the database byte order |
| DB->set_pagesize | Set the underlying database page size |
| Btree/Recno Configuration | |
| DB->set_append_recno | Set record append callback |
| DB->set_bt_compare | Set a Btree comparison function |
| DB->set_bt_minkey | Set the minimum number of keys per Btree page |
| DB->set_bt_prefix | Set a Btree prefix comparison function |
| DB->set_re_delim | Set the variable-length record delimiter |
| DB->set_re_len | Set the fixed-length record length |
| DB->set_re_pad | Set the fixed-length record pad byte |
| DB->set_re_source | Set the backing Recno text file |
| Hash Configuration | |
| DB->set_h_compare | Set a Hash comparison function |
| DB->set_h_ffactor | Set the Hash table density |
| DB->set_h_hash | Set a hashing function |
| DB->set_h_nelem | Set the Hash table size |
| Queue Configuration | |
| DB->set_q_extentsize | Set Queue database extent size |
![]() ![]()
|
Copyright (c) 1996,2008 Oracle. All rights reserved.