static int
index_compare(WT_COLLATOR *collator, WT_SESSION *session,
const WT_ITEM *key1, const WT_ITEM *key2, int *cmp)
{
WT_ITEM ikey1, pkey1, ikey2, pkey2;
(void)collator;
testutil_check(wiredtiger_struct_unpack(session,
key1->data, key1->size, "uu", &ikey1, &pkey1));
testutil_check(wiredtiger_struct_unpack(session,
key2->data, key2->size, "uu", &ikey2, &pkey2));
print_int_item("index_compare: index key1 = ", &ikey1);
print_int_item(", primary key1 = ", &pkey1);
print_int_item(", index key2 = ", &ikey2);
print_int_item(", primary key2 = ", &pkey2);
printf("\n");
if ((*cmp = compare_int_items(&ikey1, &ikey2)) != 0)
return (0);
if (pkey1.size != 0 && pkey2.size != 0)
*cmp = compare_int_items(&pkey1, &pkey2);
else if (pkey1.size != 0)
*cmp = 1;
else if (pkey2.size != 0)
*cmp = -1;
else
*cmp = 0;
return (0);
}
int
pack_ops(WT_SESSION *session)
{
int ret;
{
/*! [Get the packed size] */
size_t size;
ret = wiredtiger_struct_size(session, &size, "iSh", 42, "hello", -3);
/*! [Get the packed size] */
assert(size < 100);
}
{
/*! [Pack fields into a buffer] */
char buf[100];
ret = wiredtiger_struct_pack(
session, buf, sizeof(buf), "iSh", 42, "hello", -3);
/*! [Pack fields into a buffer] */
{
/*! [Unpack fields from a buffer] */
int i;
char *s;
short h;
ret = wiredtiger_struct_unpack(
session, buf, sizeof(buf), "iSh", &i, &s, &h);
/*! [Unpack fields from a buffer] */
}
}
return (ret);
}
static void
pack_ops(WT_SESSION *session)
{
{
/*! [Get the packed size] */
size_t size;
error_check(wiredtiger_struct_size(
session, &size, "iSh", 42, "hello", -3));
/*! [Get the packed size] */
}
{
/*! [Pack fields into a buffer] */
char buf[100];
error_check(wiredtiger_struct_pack(
session, buf, sizeof(buf), "iSh", 42, "hello", -3));
/*! [Pack fields into a buffer] */
{
/*! [Unpack fields from a buffer] */
int i;
char *s;
short h;
error_check(wiredtiger_struct_unpack(
session, buf, sizeof(buf), "iSh", &i, &s, &h));
/*! [Unpack fields from a buffer] */
}
}
}
int
main(void)
{
WT_CONNECTION *conn;
WT_SESSION *session;
int i, j, k, ret;
/*
* Create a clean test directory for this run of the test program if the
* environment variable isn't already set (as is done by make check).
*/
if (getenv("WIREDTIGER_HOME") == NULL) {
home = "WT_HOME";
ret = system("rm -rf WT_HOME && mkdir WT_HOME");
} else
home = NULL;
/* 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 == NULL ? "." : home, wiredtiger_strerror(ret));
return (EXIT_FAILURE);
}
/* 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 == NULL ? "." : home, wiredtiger_strerror(ret));
return (EXIT_FAILURE);
}
{
/*! [packing] */
size_t size;
char buf[50];
ret = wiredtiger_struct_size(session, &size, "iii", 42, 1000, -9);
if (size > sizeof(buf)) {
/* Allocate a bigger buffer. */
}
ret = wiredtiger_struct_pack(session, buf, size, "iii", 42, 1000, -9);
ret = wiredtiger_struct_unpack(session, buf, size, "iii", &i, &j, &k);
/*! [packing] */
}
/* Note: closing the connection implicitly closes open session(s). */
if ((ret = conn->close(conn, NULL)) != 0) {
fprintf(stderr, "Error closing %s: %s\n",
home == NULL ? "." : home, wiredtiger_strerror(ret));
return (EXIT_FAILURE);
}
return (EXIT_SUCCESS);
}
int main(void)
{
WT_CONNECTION *conn;
WT_SESSION *session;
char buf[50];
size_t size;
int i, j, k, 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));
/*! [packing] */
ret = wiredtiger_struct_size(session, &size, "iii", 42, 1000, -9);
if (size > sizeof(buf)) {
/* Allocate a bigger buffer. */
}
ret = wiredtiger_struct_pack(session, buf, size, "iii", 42, 1000, -9);
ret = wiredtiger_struct_unpack(session, buf, size, "iii", &i, &j, &k);
/*! [packing] */
/* 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);
}
/*
* A custom index extractor function that adds an index entry for each year of
* the given president's term.
*/
static int
my_extract(WT_EXTRACTOR *extractor, WT_SESSION *session,
const WT_ITEM *key, const WT_ITEM *value, WT_CURSOR *result_cursor)
{
uint16_t term_end, term_start, year;
char *last_name, *first_name;
/* Unused parameters */
(void)extractor;
(void)key;
/* Unpack the value. */
error_check(wiredtiger_struct_unpack(
session, value->data, value->size, "SSHH",
&last_name, &first_name, &term_start, &term_end));
/*
* We have overlapping years, so multiple records may share the same
* index key.
*/
for (year = term_start; year <= term_end; ++year) {
/*
* Note that the extract callback is called for all operations
* that update the table, not just inserts. The user sets the
* key and uses the cursor->insert() method to return the index
* key(s). WiredTiger will perform the required operation
* (such as a remove()).
*/
fprintf(stderr,
"EXTRACTOR: index op for year %" PRIu16 ": %s %s\n",
year, first_name, last_name);
result_cursor->set_key(result_cursor, year);
error_check(result_cursor->insert(result_cursor));
}
return (0);
}
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);
}
int
main(void)
{
POP_RECORD *p;
WT_CONNECTION *conn;
WT_CURSOR *cursor, *cursor2, *join_cursor, *stat_cursor;
WT_SESSION *session;
const char *country;
uint64_t recno, population;
uint16_t year;
int ret;
/*
* Create a clean test directory for this run of the test program if the
* environment variable isn't already set (as is done by make check).
*/
if (getenv("WIREDTIGER_HOME") == NULL) {
home = "WT_HOME";
ret = system("rm -rf WT_HOME && mkdir WT_HOME");
} else
home = NULL;
if ((ret = wiredtiger_open(
home, NULL, "create,statistics=(fast)", &conn)) != 0) {
fprintf(stderr, "Error connecting to %s: %s\n",
home, wiredtiger_strerror(ret));
return (ret);
}
/* Note: error checking omitted for clarity. */
ret = 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.
*/
ret = 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").
*/
ret = session->create(session,
"colgroup:poptable:main", "columns=(country,year,population)");
ret = session->create(session,
"colgroup:poptable:population", "columns=(population)");
/*! [Create a table with column groups] */
/*! [Create an index] */
/* Create an index with a simple key. */
ret = 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). */
ret = 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. */
ret = session->create(session,
"index:poptable:immutable_year", "columns=(year),immutable");
/*! [Create an immutable index] */
/* Insert the records into the table. */
ret = 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);
ret = cursor->insert(cursor);
}
ret = cursor->close(cursor);
/* Update records in the table. */
ret = session->open_cursor(session,
"table:poptable", NULL, NULL, &cursor);
while ((ret = cursor->next(cursor)) == 0) {
ret = cursor->get_key(cursor, &recno);
ret = cursor->get_value(cursor, &country, &year, &population);
cursor->set_value(cursor, country, year, population + 1);
ret = cursor->update(cursor);
}
ret = cursor->close(cursor);
/* List the records in the table. */
ret = session->open_cursor(session,
"table:poptable", NULL, NULL, &cursor);
while ((ret = cursor->next(cursor)) == 0) {
ret = cursor->get_key(cursor, &recno);
ret = cursor->get_value(cursor, &country, &year, &population);
printf("ID %" PRIu64, recno);
printf(
": country %s, year %" PRIu16 ", population %" PRIu64 "\n",
country, year, population);
}
ret = cursor->close(cursor);
/*! [List the records in the table using raw mode.] */
/* List the records in the table using raw mode. */
ret = session->open_cursor(session,
"table:poptable", NULL, "raw", &cursor);
while ((ret = cursor->next(cursor)) == 0) {
WT_ITEM key, value;
ret = cursor->get_key(cursor, &key);
ret = wiredtiger_struct_unpack(session,
key.data, key.size, "r", &recno);
printf("ID %" PRIu64, recno);
ret = cursor->get_value(cursor, &value);
ret = wiredtiger_struct_unpack(session,
value.data, value.size,
"5sHQ", &country, &year, &population);
printf(
": country %s, year %" PRIu16 ", population %" PRIu64 "\n",
country, year, population);
}
/*! [List the records in the table using raw mode.] */
ret = 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.
*/
ret = session->open_cursor(
session, "colgroup:poptable:main", NULL, NULL, &cursor);
cursor->set_key(cursor, 2);
if ((ret = cursor->search(cursor)) == 0) {
ret = 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] */
ret = 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.
*/
ret = session->open_cursor(session,
"colgroup:poptable:population", NULL, NULL, &cursor);
cursor->set_key(cursor, 2);
if ((ret = cursor->search(cursor)) == 0) {
ret = cursor->get_value(cursor, &population);
printf("ID 2: population %" PRIu64 "\n", population);
}
/*! [Read population from the standalone column group] */
ret = cursor->close(cursor);
/*! [Search in a simple index] */
/* Search in a simple index. */
ret = session->open_cursor(session,
"index:poptable:country", NULL, NULL, &cursor);
cursor->set_key(cursor, "AU\0\0\0");
ret = cursor->search(cursor);
ret = cursor->get_value(cursor, &country, &year, &population);
printf("AU: country %s, year %" PRIu16 ", population %" PRIu64 "\n",
country, year, population);
/*! [Search in a simple index] */
ret = cursor->close(cursor);
/*! [Search in a composite index] */
/* Search in a composite index. */
ret = session->open_cursor(session,
"index:poptable:country_plus_year", NULL, NULL, &cursor);
cursor->set_key(cursor, "USA\0\0", (uint16_t)1900);
ret = cursor->search(cursor);
ret = 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] */
ret = cursor->close(cursor);
/*! [Return a subset of values from the table] */
/*
* Use a projection to return just the table's country and year
* columns.
*/
ret = session->open_cursor(session,
"table:poptable(country,year)", NULL, NULL, &cursor);
while ((ret = cursor->next(cursor)) == 0) {
ret = cursor->get_value(cursor, &country, &year);
printf("country %s, year %" PRIu16 "\n", country, year);
}
/*! [Return a subset of values from the table] */
ret = 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.
*/
ret = session->open_cursor(session,
"table:poptable(country,year)", NULL, "raw", &cursor);
while ((ret = cursor->next(cursor)) == 0) {
WT_ITEM value;
ret = cursor->get_value(cursor, &value);
ret = wiredtiger_struct_unpack(
session, value.data, value.size, "5sH", &country, &year);
printf("country %s, year %" PRIu16 "\n", country, year);
}
/*! [Return a subset of values from the table using raw mode] */
ret = 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.
*/
ret = session->open_cursor(session,
"index:poptable:country_plus_year(id)", NULL, NULL, &cursor);
while ((ret = cursor->next(cursor)) == 0) {
ret = cursor->get_key(cursor, &country, &year);
ret = cursor->get_value(cursor, &recno);
printf("row ID %" PRIu64 ": country %s, year %" PRIu16 "\n",
recno, country, year);
}
/*! [Return the table's record number key using an index] */
ret = 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.
*/
ret = session->open_cursor(session,
"index:poptable:country_plus_year(population)",
NULL, NULL, &cursor);
while ((ret = cursor->next(cursor)) == 0) {
ret = cursor->get_key(cursor, &country, &year);
ret = cursor->get_value(cursor, &population);
printf("population %" PRIu64 ": country %s, year %" PRIu16 "\n",
population, country, year);
}
/*! [Return a subset of the value columns from an index] */
ret = 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.
*/
ret = session->open_cursor(session,
"index:poptable:country_plus_year()", NULL, NULL, &cursor);
while ((ret = cursor->next(cursor)) == 0) {
ret = cursor->get_key(cursor, &country, &year);
printf("country %s, year %" PRIu16 "\n", country, year);
}
/*! [Access only the index] */
ret = cursor->close(cursor);
/*! [Join cursors] */
/* Open cursors needed by the join. */
ret = session->open_cursor(session,
"join:table:poptable", NULL, NULL, &join_cursor);
ret = session->open_cursor(session,
"index:poptable:country", NULL, NULL, &cursor);
ret = session->open_cursor(session,
"index:poptable:immutable_year", NULL, NULL, &cursor2);
/* select values WHERE country == "AU" AND year > 1900 */
cursor->set_key(cursor, "AU\0\0\0");
ret = cursor->search(cursor);
ret = session->join(session, join_cursor, cursor,
"compare=eq,count=10");
cursor2->set_key(cursor2, (uint16_t)1900);
ret = cursor2->search(cursor2);
ret = session->join(session, join_cursor, cursor2,
"compare=gt,count=10,strategy=bloom");
/* List the values that are joined */
while ((ret = join_cursor->next(join_cursor)) == 0) {
ret = join_cursor->get_key(join_cursor, &recno);
ret = join_cursor->get_value(join_cursor, &country, &year,
&population);
printf("ID %" PRIu64, recno);
printf(
": country %s, year %" PRIu16 ", population %" PRIu64 "\n",
country, year, population);
}
/*! [Join cursors] */
/*! [Statistics cursor join cursor] */
ret = session->open_cursor(session,
"statistics:join",
join_cursor, NULL, &stat_cursor);
/*! [Statistics cursor join cursor] */
ret = stat_cursor->close(stat_cursor);
ret = join_cursor->close(join_cursor);
ret = cursor2->close(cursor2);
ret = cursor->close(cursor);
ret = conn->close(conn, NULL);
return (ret);
}
