/*- * Public Domain 2014-present MongoDB, Inc. * Public Domain 2008-2014 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_schema.c * This is an example application demonstrating how to create and access * tables using a schema. */ #include static const char *home; /*! [schema declaration] */ /* The C struct for the data we are storing in a WiredTiger table. */ typedef struct { char country[5]; uint16_t year; uint64_t population; } POP_RECORD; static POP_RECORD pop_data[] = {{"AU", 1900, 4000000}, {"AU", 1950, 8267337}, {"AU", 2000, 19053186}, {"CAN", 1900, 5500000}, {"CAN", 1950, 14011422}, {"CAN", 2000, 31099561}, {"UK", 1900, 369000000}, {"UK", 1950, 50127000}, {"UK", 2000, 59522468}, {"USA", 1900, 76212168}, {"USA", 1950, 150697361}, {"USA", 2000, 301279593}, {"", 0, 0}}; /*! [schema declaration] */ int main(int argc, char *argv[]) { POP_RECORD *p; WT_CONNECTION *conn; WT_CURSOR *country_cursor, *country_cursor2, *cursor, *join_cursor, *stat_cursor, *subjoin_cursor, *year_cursor; WT_SESSION *session; const char *country; uint64_t recno, population; uint16_t year; int ret; home = example_setup(argc, argv); error_check(wiredtiger_open(home, NULL, "create,statistics=(fast)", &conn)); error_check(conn->open_session(conn, NULL, NULL, &session)); /*! [Create a table with column groups] */ /* * Create the population table. Keys are record numbers, the format for values is (5-byte * string, uint16_t, uint64_t). See ::wiredtiger_struct_pack for details of the format strings. */ error_check(session->create(session, "table:poptable", "key_format=r,value_format=5sHQ,columns=(id,country,year,population),colgroups=(main," "population)")); /* * Create two column groups: a primary column group with the country code, year and population * (named "main"), and a population column group with the population by itself (named * "population"). */ error_check( session->create(session, "colgroup:poptable:main", "columns=(country,year,population)")); error_check(session->create(session, "colgroup:poptable:population", "columns=(population)")); /*! [Create a table with column groups] */ /*! [Create an index] */ /* Create an index with a simple key. */ error_check(session->create(session, "index:poptable:country", "columns=(country)")); /*! [Create an index] */ /*! [Create an index with a composite key] */ /* Create an index with a composite key (country,year). */ error_check( session->create(session, "index:poptable:country_plus_year", "columns=(country,year)")); /*! [Create an index with a composite key] */ /*! [Create an immutable index] */ /* Create an immutable index. */ error_check( session->create(session, "index:poptable:immutable_year", "columns=(year),immutable")); /*! [Create an immutable index] */ /* Insert the records into the table. */ error_check(session->open_cursor(session, "table:poptable", NULL, "append", &cursor)); for (p = pop_data; p->year != 0; p++) { cursor->set_value(cursor, p->country, p->year, p->population); error_check(cursor->insert(cursor)); } error_check(cursor->close(cursor)); /* Update records in the table. */ error_check(session->open_cursor(session, "table:poptable", NULL, NULL, &cursor)); while ((ret = cursor->next(cursor)) == 0) { error_check(cursor->get_key(cursor, &recno)); error_check(cursor->get_value(cursor, &country, &year, &population)); cursor->set_value(cursor, country, year, population + 1); error_check(cursor->update(cursor)); } scan_end_check(ret == WT_NOTFOUND); error_check(cursor->close(cursor)); /* List the records in the table. */ error_check(session->open_cursor(session, "table:poptable", NULL, NULL, &cursor)); while ((ret = cursor->next(cursor)) == 0) { error_check(cursor->get_key(cursor, &recno)); error_check(cursor->get_value(cursor, &country, &year, &population)); printf("ID %" PRIu64, recno); printf( ": country %s, year %" PRIu16 ", population %" PRIu64 "\n", country, year, population); } scan_end_check(ret == WT_NOTFOUND); error_check(cursor->close(cursor)); /*! [List the records in the table using raw mode.] */ /* List the records in the table using raw mode. */ error_check(session->open_cursor(session, "table:poptable", NULL, "raw", &cursor)); while ((ret = cursor->next(cursor)) == 0) { WT_ITEM key, value; error_check(cursor->get_key(cursor, &key)); error_check(wiredtiger_struct_unpack(session, key.data, key.size, "r", &recno)); printf("ID %" PRIu64, recno); error_check(cursor->get_value(cursor, &value)); error_check(wiredtiger_struct_unpack( session, value.data, value.size, "5sHQ", &country, &year, &population)); printf( ": country %s, year %" PRIu16 ", population %" PRIu64 "\n", country, year, population); } scan_end_check(ret == WT_NOTFOUND); /*! [List the records in the table using raw mode.] */ error_check(cursor->close(cursor)); /*! [Read population from the primary column group] */ /* * Open a cursor on the main column group, and return the information for a particular country. */ error_check(session->open_cursor(session, "colgroup:poptable:main", NULL, NULL, &cursor)); cursor->set_key(cursor, 2); error_check(cursor->search(cursor)); error_check(cursor->get_value(cursor, &country, &year, &population)); printf( "ID 2: country %s, year %" PRIu16 ", population %" PRIu64 "\n", country, year, population); /*! [Read population from the primary column group] */ error_check(cursor->close(cursor)); /*! [Read population from the standalone column group] */ /* * Open a cursor on the population column group, and return the population of a particular * country. */ error_check(session->open_cursor(session, "colgroup:poptable:population", NULL, NULL, &cursor)); cursor->set_key(cursor, 2); error_check(cursor->search(cursor)); error_check(cursor->get_value(cursor, &population)); printf("ID 2: population %" PRIu64 "\n", population); /*! [Read population from the standalone column group] */ error_check(cursor->close(cursor)); /*! [Search in a simple index] */ /* Search in a simple index. */ error_check(session->open_cursor(session, "index:poptable:country", NULL, NULL, &cursor)); cursor->set_key(cursor, "AU\0\0\0"); error_check(cursor->search(cursor)); error_check(cursor->get_value(cursor, &country, &year, &population)); printf("AU: country %s, year %" PRIu16 ", population %" PRIu64 "\n", country, year, population); /*! [Search in a simple index] */ error_check(cursor->close(cursor)); /*! [Search in a composite index] */ /* Search in a composite index. */ error_check( session->open_cursor(session, "index:poptable:country_plus_year", NULL, NULL, &cursor)); cursor->set_key(cursor, "USA\0\0", (uint16_t)1900); error_check(cursor->search(cursor)); error_check(cursor->get_value(cursor, &country, &year, &population)); printf( "US 1900: country %s, year %" PRIu16 ", population %" PRIu64 "\n", country, year, population); /*! [Search in a composite index] */ error_check(cursor->close(cursor)); /*! [Return a subset of values from the table] */ /* * Use a projection to return just the table's country and year columns. */ error_check(session->open_cursor(session, "table:poptable(country,year)", NULL, NULL, &cursor)); while ((ret = cursor->next(cursor)) == 0) { error_check(cursor->get_value(cursor, &country, &year)); printf("country %s, year %" PRIu16 "\n", country, year); } /*! [Return a subset of values from the table] */ scan_end_check(ret == WT_NOTFOUND); error_check(cursor->close(cursor)); /*! [Return a subset of values from the table using raw mode] */ /* * Use a projection to return just the table's country and year columns, using raw mode. */ error_check( session->open_cursor(session, "table:poptable(country,year)", NULL, "raw", &cursor)); while ((ret = cursor->next(cursor)) == 0) { WT_ITEM value; error_check(cursor->get_value(cursor, &value)); error_check( wiredtiger_struct_unpack(session, value.data, value.size, "5sH", &country, &year)); printf("country %s, year %" PRIu16 "\n", country, year); } scan_end_check(ret == WT_NOTFOUND); /*! [Return a subset of values from the table using raw mode] */ error_check(cursor->close(cursor)); /*! [Return the table's record number key using an index] */ /* * Use a projection to return just the table's record number key from an index. */ error_check( session->open_cursor(session, "index:poptable:country_plus_year(id)", NULL, NULL, &cursor)); while ((ret = cursor->next(cursor)) == 0) { error_check(cursor->get_key(cursor, &country, &year)); error_check(cursor->get_value(cursor, &recno)); printf("row ID %" PRIu64 ": country %s, year %" PRIu16 "\n", recno, country, year); } scan_end_check(ret == WT_NOTFOUND); /*! [Return the table's record number key using an index] */ error_check(cursor->close(cursor)); /*! [Return a subset of the value columns from an index] */ /* * Use a projection to return just the population column from an index. */ error_check(session->open_cursor( session, "index:poptable:country_plus_year(population)", NULL, NULL, &cursor)); while ((ret = cursor->next(cursor)) == 0) { error_check(cursor->get_key(cursor, &country, &year)); error_check(cursor->get_value(cursor, &population)); printf("population %" PRIu64 ": country %s, year %" PRIu16 "\n", population, country, year); } scan_end_check(ret == WT_NOTFOUND); /*! [Return a subset of the value columns from an index] */ error_check(cursor->close(cursor)); /*! [Access only the index] */ /* * Use a projection to avoid accessing any other column groups when using an index: supply an * empty list of value columns. */ error_check( session->open_cursor(session, "index:poptable:country_plus_year()", NULL, NULL, &cursor)); while ((ret = cursor->next(cursor)) == 0) { error_check(cursor->get_key(cursor, &country, &year)); printf("country %s, year %" PRIu16 "\n", country, year); } scan_end_check(ret == WT_NOTFOUND); /*! [Access only the index] */ error_check(cursor->close(cursor)); /*! [Join cursors] */ /* Open cursors needed by the join. */ error_check(session->open_cursor(session, "join:table:poptable", NULL, NULL, &join_cursor)); error_check( session->open_cursor(session, "index:poptable:country", NULL, NULL, &country_cursor)); error_check( session->open_cursor(session, "index:poptable:immutable_year", NULL, NULL, &year_cursor)); /* select values WHERE country == "AU" AND year > 1900 */ country_cursor->set_key(country_cursor, "AU\0\0\0"); error_check(country_cursor->search(country_cursor)); error_check(session->join(session, join_cursor, country_cursor, "compare=eq,count=10")); year_cursor->set_key(year_cursor, (uint16_t)1900); error_check(year_cursor->search(year_cursor)); error_check( session->join(session, join_cursor, year_cursor, "compare=gt,count=10,strategy=bloom")); /* List the values that are joined */ while ((ret = join_cursor->next(join_cursor)) == 0) { error_check(join_cursor->get_key(join_cursor, &recno)); error_check(join_cursor->get_value(join_cursor, &country, &year, &population)); printf("ID %" PRIu64, recno); printf( ": country %s, year %" PRIu16 ", population %" PRIu64 "\n", country, year, population); } scan_end_check(ret == WT_NOTFOUND); /*! [Join cursors] */ /*! [Statistics cursor join cursor] */ error_check(session->open_cursor(session, "statistics:join", join_cursor, NULL, &stat_cursor)); /*! [Statistics cursor join cursor] */ error_check(stat_cursor->close(stat_cursor)); error_check(join_cursor->close(join_cursor)); error_check(year_cursor->close(year_cursor)); error_check(country_cursor->close(country_cursor)); /*! [Complex join cursors] */ /* Open cursors needed by the join. */ error_check(session->open_cursor(session, "join:table:poptable", NULL, NULL, &join_cursor)); error_check(session->open_cursor(session, "join:table:poptable", NULL, NULL, &subjoin_cursor)); error_check( session->open_cursor(session, "index:poptable:country", NULL, NULL, &country_cursor)); error_check( session->open_cursor(session, "index:poptable:country", NULL, NULL, &country_cursor2)); error_check( session->open_cursor(session, "index:poptable:immutable_year", NULL, NULL, &year_cursor)); /* * select values WHERE (country == "AU" OR country == "UK") * AND year > 1900 * * First, set up the join representing the country clause. */ country_cursor->set_key(country_cursor, "AU\0\0\0"); error_check(country_cursor->search(country_cursor)); error_check( session->join(session, subjoin_cursor, country_cursor, "operation=or,compare=eq,count=10")); country_cursor2->set_key(country_cursor2, "UK\0\0\0"); error_check(country_cursor2->search(country_cursor2)); error_check( session->join(session, subjoin_cursor, country_cursor2, "operation=or,compare=eq,count=10")); /* Join that to the top join, and add the year clause */ error_check(session->join(session, join_cursor, subjoin_cursor, NULL)); year_cursor->set_key(year_cursor, (uint16_t)1900); error_check(year_cursor->search(year_cursor)); error_check( session->join(session, join_cursor, year_cursor, "compare=gt,count=10,strategy=bloom")); /* List the values that are joined */ while ((ret = join_cursor->next(join_cursor)) == 0) { error_check(join_cursor->get_key(join_cursor, &recno)); error_check(join_cursor->get_value(join_cursor, &country, &year, &population)); printf("ID %" PRIu64, recno); printf( ": country %s, year %" PRIu16 ", population %" PRIu64 "\n", country, year, population); } scan_end_check(ret == WT_NOTFOUND); /*! [Complex join cursors] */ error_check(join_cursor->close(join_cursor)); error_check(subjoin_cursor->close(subjoin_cursor)); error_check(country_cursor->close(country_cursor)); error_check(country_cursor2->close(country_cursor2)); error_check(year_cursor->close(year_cursor)); error_check(conn->close(conn, NULL)); return (EXIT_SUCCESS); }