Shows some common cursor types and operations.
/*- * Copyright (c) 2008-2012 WiredTiger, Inc. * * This is free and unencumbered software released into the public domain. * * Anyone is free to copy, modify, publish, use, compile, sell, or * distribute this software, either in source code form or as a compiled * binary, for any purpose, commercial or non-commercial, and by any * means. * * In jurisdictions that recognize copyright laws, the author or authors * of this software dedicate any and all copyright interest in the * software to the public domain. We make this dedication for the benefit * of the public at large and to the detriment of our heirs and * successors. We intend this dedication to be an overt act of * relinquishment in perpetuity of all present and future rights to this * software under copyright law. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR * OTHER DEALINGS IN THE SOFTWARE. * * ex_cursor.c * This is an example demonstrating some cursor types and operations. */ #include <stdio.h> #include <string.h> #include <wiredtiger.h> int cursor_reset(WT_CURSOR *cursor); int cursor_forward_scan(WT_CURSOR *cursor); int cursor_reverse_scan(WT_CURSOR *cursor); int cursor_search(WT_CURSOR *cursor); int cursor_search_near(WT_CURSOR *cursor); int cursor_insert(WT_CURSOR *cursor); int cursor_update(WT_CURSOR *cursor); int cursor_remove(WT_CURSOR *cursor); const char *home = "WT_TEST"; int cursor_forward_scan(WT_CURSOR *cursor) { const char *key, *value; int ret; while ((ret = cursor->next(cursor)) == 0) { ret = cursor->get_key(cursor, &key); ret = cursor->get_value(cursor, &value); } return (ret); } int cursor_reverse_scan(WT_CURSOR *cursor) { const char *key, *value; int ret; while ((ret = cursor->prev(cursor)) == 0) { ret = cursor->get_key(cursor, &key); ret = cursor->get_value(cursor, &value); } return (ret); } int cursor_reset(WT_CURSOR *cursor) { return (cursor->reset(cursor)); } int cursor_search(WT_CURSOR *cursor) { const char *value; int ret; cursor->set_key(cursor, "foo"); if ((ret = cursor->search(cursor)) != 0) ret = cursor->get_value(cursor, &value); return (ret); } int cursor_search_near(WT_CURSOR *cursor) { const char *key, *value; int exact, ret; cursor->set_key(cursor, "foo"); if ((ret = cursor->search_near(cursor, &exact)) == 0) { switch (exact) { case -1: /* Returned key smaller than search key */ ret = cursor->get_key(cursor, &key); break; case 0: /* Exact match found */ break; case 1: /* Returned key larger than search key */ ret = cursor->get_key(cursor, &key); break; } ret = cursor->get_value(cursor, &value); } return (ret); } int cursor_insert(WT_CURSOR *cursor) { cursor->set_key(cursor, "foo"); cursor->set_value(cursor, "bar"); return (cursor->insert(cursor)); } int cursor_update(WT_CURSOR *cursor) { cursor->set_key(cursor, "foo"); cursor->set_value(cursor, "newbar"); return (cursor->update(cursor)); } int cursor_remove(WT_CURSOR *cursor) { cursor->set_key(cursor, "foo"); return (cursor->remove(cursor)); } int main(void) { WT_CONNECTION *conn; WT_CURSOR *cursor; WT_SESSION *session; int ret; /* Open a connection to the database, creating it if necessary. */ if ((ret = wiredtiger_open(home, NULL, "create", &conn)) != 0) fprintf(stderr, "Error connecting to %s: %s\n", home, wiredtiger_strerror(ret)); /* Open a session for the current thread's work. */ if ((ret = conn->open_session(conn, NULL, NULL, &session)) != 0) fprintf(stderr, "Error opening a session on %s: %s\n", home, wiredtiger_strerror(ret)); ret = session->create(session, "table:world", "key_format=r,value_format=5sii," "columns=(id,country,population,area)"); ret = session->open_cursor(session, "table:world", NULL, NULL, &cursor); ret = session->open_cursor(session, "table:world(country,population)", NULL, NULL, &cursor); ret = session->open_cursor(session, "statistics:", NULL, NULL, &cursor); /* Create a simple string table to illustrate basic operations. */ ret = session->create(session, "table:map", "key_format=S,value_format=S"); ret = session->open_cursor(session, "table:map", NULL, NULL, &cursor); ret = cursor_insert(cursor); ret = cursor_reset(cursor); ret = cursor_forward_scan(cursor); ret = cursor_reset(cursor); ret = cursor_reverse_scan(cursor); ret = cursor_update(cursor); ret = cursor_remove(cursor); ret = cursor->close(cursor); /* Note: closing the connection implicitly closes open session(s). */ if ((ret = conn->close(conn, NULL)) != 0) fprintf(stderr, "Error connecting to %s: %s\n", home, wiredtiger_strerror(ret)); return (ret); }