Mojo::Pg::Database(3pm)

1Mojo::Pg::Database(3) User Contributed Perl DocumentationMojo::Pg::Database(3)
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NAME

6       Mojo::Pg::Database - Database
7

SYNOPSIS

9         use Mojo::Pg::Database;
10
11         my $db = Mojo::Pg::Database->new(pg => $pg, dbh => $dbh);
12         $db->query('SELECT * FROM foo') ->hashes->map(sub { $_->{bar} })->join("\n")->say;
13

DESCRIPTION

15       Mojo::Pg::Database is a container for DBD::Pg database handles used by
16       Mojo::Pg.
17

EVENTS

19       Mojo::Pg::Database inherits all events from Mojo::EventEmitter and can
20       emit the following new ones.
21
22   close
23         $db->on(close => sub ($db) {
24           ...
25         });
26
27       Emitted when the database connection gets closed while waiting for
28       notifications.
29
30   notification
31         $db->on(notification => sub ($db, $name, $pid, $payload) {
32           ...
33         });
34
35       Emitted when a notification has been received.
36

ATTRIBUTES

38       Mojo::Pg::Database implements the following attributes.
39
40   dbh
41         my $dbh = $db->dbh;
42         $db     = $db->dbh($dbh);
43
44       DBD::Pg database handle used for all queries.
45
46         # Use DBI utility methods
47         my $quoted = $db->dbh->quote_identifier('foo.bar');
48
49   pg
50         my $pg = $db->pg;
51         $db    = $db->pg(Mojo::Pg->new);
52
53       Mojo::Pg object this database belongs to. Note that this attribute is
54       weakened.
55
56   results_class
57         my $class = $db->results_class;
58         $db       = $db->results_class('MyApp::Results');
59
60       Class to be used by "query", defaults to Mojo::Pg::Results. Note that
61       this class needs to have already been loaded before "query" is called.
62

METHODS

64       Mojo::Pg::Database inherits all methods from Mojo::EventEmitter and
65       implements the following new ones.
66
67   begin
68         my $tx = $db->begin;
69
70       Begin transaction and return Mojo::Pg::Transaction object, which will
71       automatically roll back the transaction unless "commit" in
72       Mojo::Pg::Transaction has been called before it is destroyed.
73
74         # Insert rows in a transaction
75         eval {
76           my $tx = $db->begin;
77           $db->insert('frameworks', {name => 'Catalyst'});
78           $db->insert('frameworks', {name => 'Mojolicious'});
79           $tx->commit;
80         };
81         say $@ if $@;
82
83   delete
84         my $results = $db->delete($table, \%where, \%options);
85
86       Generate a "DELETE" statement with "abstract" in Mojo::Pg (usually an
87       SQL::Abstract::Pg object) and execute it with "query". You can also
88       append a callback to perform operations non-blocking.
89
90         $db->delete(some_table => sub ($db, $err, $results) {
91           ...
92         });
93         Mojo::IOLoop->start unless Mojo::IOLoop->is_running;
94
95       Use all the same argument variations you would pass to the "delete"
96       method of SQL::Abstract.
97
98         # "DELETE FROM some_table"
99         $db->delete('some_table');
100
101         # "DELETE FROM some_table WHERE foo = 'bar'"
102         $db->delete('some_table', {foo => 'bar'});
103
104         # "DELETE from some_table WHERE foo LIKE '%test%'"
105         $db->delete('some_table', {foo => {-like => '%test%'}});
106
107         # "DELETE FROM some_table WHERE foo = 'bar' RETURNING id"
108         $db->delete('some_table', {foo => 'bar'}, {returning => 'id'});
109
110   delete_p
111         my $promise = $db->delete_p($table, \%where, \%options);
112
113       Same as "delete", but performs all operations non-blocking and returns
114       a Mojo::Promise object instead of accepting a callback.
115
116         $db->delete_p('some_table')->then(sub ($results) {
117           ...
118         })->catch(sub ($err) {
119           ...
120         })->wait;
121
122   disconnect
123         $db->disconnect;
124
125       Disconnect "dbh" and prevent it from getting reused.
126
127   dollar_only
128         $db = $db->dollar_only;
129
130       Activate "pg_placeholder_dollaronly" for next "query" call and allow
131       "?" to be used as an operator.
132
133         # Check for a key in a JSON document
134         $db->dollar_only->query('SELECT * FROM foo WHERE bar ? $1', 'baz')
135           ->expand->hashes->map(sub { $_->{bar}{baz} })->join("\n")->say;
136
137   insert
138         my $results = $db->insert($table, \@values || \%fieldvals, \%options);
139
140       Generate an "INSERT" statement with "abstract" in Mojo::Pg (usually an
141       SQL::Abstract::Pg object) and execute it with "query". You can also
142       append a callback to perform operations non-blocking.
143
144         $db->insert(some_table => {foo => 'bar'} => sub ($db, $err, $results) {
145           ...
146         });
147         Mojo::IOLoop->start unless Mojo::IOLoop->is_running;
148
149       Use all the same argument variations you would pass to the "insert"
150       method of SQL::Abstract.
151
152         # "INSERT INTO some_table (foo, baz) VALUES ('bar', 'yada')"
153         $db->insert('some_table', {foo => 'bar', baz => 'yada'});
154
155         # "INSERT INTO some_table (foo) VALUES ({1,2,3})"
156         $db->insert('some_table', {foo => [1, 2, 3]});
157
158         # "INSERT INTO some_table (foo) VALUES ('bar') RETURNING id"
159         $db->insert('some_table', {foo => 'bar'}, {returning => 'id'});
160
161         # "INSERT INTO some_table (foo) VALUES ('bar') RETURNING id, foo"
162         $db->insert('some_table', {foo => 'bar'}, {returning => ['id', 'foo']});
163
164       As well as some PostgreSQL specific extensions added by
165       SQL::Abstract::Pg.
166
167         # "INSERT INTO some_table (foo) VALUES ('{"test":23}')"
168         $db->insert('some_table', {foo => {-json => {test => 23}}});
169
170         # "INSERT INTO some_table (foo) VALUES ('bar') ON CONFLICT DO NOTHING"
171         $db->insert('some_table', {foo => 'bar'}, {on_conflict => undef});
172
173       Including operations commonly referred to as "upsert".
174
175         # "INSERT INTO t (a) VALUES ('b') ON CONFLICT (a) DO UPDATE SET a = 'c'"
176         $db->insert('t', {a => 'b'}, {on_conflict => [a => {a => 'c'}]});
177
178         # "INSERT INTO t (a, b) VALUES ('c', 'd') ON CONFLICT (a, b) DO UPDATE SET a = 'e'"
179         $db->insert('t', {a => 'c', b => 'd'}, {on_conflict => [['a', 'b'] => {a => 'e'}]});
180
181   insert_p
182         my $promise = $db->insert_p($table, \@values || \%fieldvals, \%options);
183
184       Same as "insert", but performs all operations non-blocking and returns
185       a Mojo::Promise object instead of accepting a callback.
186
187         $db->insert_p(some_table => {foo => 'bar'})->then(sub ($results) {
188           ...
189         })->catch(sub ($err) {
190           ...
191         })->wait;
192
193   is_listening
194         my $bool = $db->is_listening;
195
196       Check if "dbh" is listening for notifications.
197
198   listen
199         $db = $db->listen('foo');
200
201       Subscribe to a channel and receive "notification" events when the
202       Mojo::IOLoop event loop is running.
203
204   notify
205         $db = $db->notify('foo');
206         $db = $db->notify(foo => 'bar');
207
208       Notify a channel.
209
210   pid
211         my $pid = $db->pid;
212
213       Return the process id of the backend server process.
214
215   ping
216         my $bool = $db->ping;
217
218       Check database connection.
219
220   query
221         my $results = $db->query('SELECT * FROM foo');
222         my $results = $db->query('INSERT INTO foo VALUES (?, ?, ?)', @values);
223         my $results = $db->query('SELECT ?::JSON AS foo', {-json => {bar => 'baz'}});
224
225       Execute a blocking SQL
226       <http://www.postgresql.org/docs/current/static/sql.html> statement and
227       return a results object based on "results_class" (which is usually
228       Mojo::Pg::Results) with the query results. The DBD::Pg statement handle
229       will be automatically reused when it is not active anymore, to increase
230       the performance of future queries. You can also append a callback to
231       perform operations non-blocking.
232
233         $db->query('INSERT INTO foo VALUES (?, ?, ?)' => @values => sub ($db, $err, $results) {
234           ...
235         });
236         Mojo::IOLoop->start unless Mojo::IOLoop->is_running;
237
238       Hash reference arguments containing a value named "-json" or "json"
239       will be encoded to JSON text with "to_json" in Mojo::JSON. To
240       accomplish the reverse, you can use the method "expand" in
241       Mojo::Pg::Results, which automatically decodes all fields of the types
242       "json" and "jsonb" with "from_json" in Mojo::JSON to Perl values.
243
244         # "I ♥ Mojolicious!"
245         $db->query('SELECT ?::JSONB AS foo', {-json => {bar => 'I ♥ Mojolicious!'}}) ->expand->hash->{foo}{bar};
246
247       Hash reference arguments containing values named "type" and "value" can
248       be used to bind specific DBD::Pg data types to placeholders.
249
250         # Insert binary data
251         use DBD::Pg ':pg_types';
252         $db->query('INSERT INTO bar VALUES (?)', {type => PG_BYTEA, value => $bytes});
253
254   query_p
255         my $promise = $db->query_p('SELECT * FROM foo');
256
257       Same as "query", but performs all operations non-blocking and returns a
258       Mojo::Promise object instead of accepting a callback.
259
260         $db->query_p('INSERT INTO foo VALUES (?, ?, ?)' => @values)->then(sub ($results) {
261           ...
262         })->catch(sub ($err) {
263           ...
264         })->wait;
265
266   select
267         my $results = $db->select($source, $fields, $where, \%options);
268
269       Generate a "SELECT" statement with "abstract" in Mojo::Pg (usually an
270       SQL::Abstract::Pg object) and execute it with "query". You can also
271       append a callback to perform operations non-blocking.
272
273         $db->select(some_table => ['foo'] => {bar => 'yada'} => sub ($db, $err, $results) {
274           ...
275         });
276         Mojo::IOLoop->start unless Mojo::IOLoop->is_running;
277
278       Use all the same argument variations you would pass to the "select"
279       method of SQL::Abstract.
280
281         # "SELECT * FROM some_table"
282         $db->select('some_table');
283
284         # "SELECT id, foo FROM some_table"
285         $db->select('some_table', ['id', 'foo']);
286
287         # "SELECT * FROM some_table WHERE foo = 'bar'"
288         $db->select('some_table', undef, {foo => 'bar'});
289
290         # "SELECT * FROM some_table WHERE foo LIKE '%test%'"
291         $db->select('some_table', undef, {foo => {-like => '%test%'}});
292
293       As well as some PostgreSQL specific extensions added by
294       SQL::Abstract::Pg.
295
296         # "SELECT * FROM foo JOIN bar ON (bar.foo_id = foo.id)"
297         $db->select(['foo', ['bar', foo_id => 'id']]);
298
299         # "SELECT * FROM foo LEFT JOIN bar ON (bar.foo_id = foo.id)"
300         $db->select(['foo', [-left => 'bar', foo_id => 'id']]);
301
302         # "SELECT foo AS bar FROM some_table"
303         $db->select('some_table', [[foo => 'bar']]);
304
305         # "SELECT * FROM some_table WHERE foo = '[1,2,3]'"
306         $db->select('some_table', '*', {foo => {'=' => {-json => [1, 2, 3]}}});
307
308         # "SELECT EXTRACT(EPOCH FROM foo) AS foo, bar FROM some_table"
309         $db->select('some_table', [\'extract(epoch from foo) AS foo', 'bar']);
310
311         # "SELECT 'test' AS foo, bar FROM some_table"
312         $db->select('some_table', [\['? AS foo', 'test'], 'bar']);
313
314       Including a new last argument to pass many new options.
315
316         # "SELECT * FROM some_table WHERE foo = 'bar' ORDER BY id DESC"
317         $db->select('some_table', '*', {foo => 'bar'}, {order_by => {-desc => 'id'}});
318
319         # "SELECT * FROM some_table LIMIT 10 OFFSET 20"
320         $db->select('some_table', '*', undef, {limit => 10, offset => 20});
321
322         # "SELECT * FROM some_table WHERE foo = 23 GROUP BY foo, bar"
323         $db->select('some_table', '*', {foo => 23}, {group_by => ['foo', 'bar']});
324
325         # "SELECT * FROM t WHERE a = 'b' GROUP BY c HAVING d = 'e'"
326         $db->select('t', '*', {a => 'b'}, {group_by => ['c'], having => {d => 'e'}});
327
328         # "SELECT * FROM some_table WHERE id = 1 FOR UPDATE"
329         $db->select('some_table', '*', {id => 1}, {for => 'update'});
330
331         # "SELECT * FROM some_table WHERE id = 1 FOR UPDATE SKIP LOCKED"
332         $db->select('some_table', '*', {id => 1}, {for => \'update skip locked'});
333
334   select_p
335         my $promise = $db->select_p($source, $fields, $where, \%options);
336
337       Same as "select", but performs all operations non-blocking and returns
338       a Mojo::Promise object instead of accepting a callback.
339
340         $db->select_p(some_table => ['foo'] => {bar => 'yada'})->then(sub ($results) {
341           ...
342         })->catch(sub ($err) {
343           ...
344         })->wait;
345
346   tables
347         my $tables = $db->tables;
348
349       Return table and view names for this database, that are visible to the
350       current user and not internal, as an array reference.
351
352         # Names of all tables
353         say for @{$db->tables};
354
355   unlisten
356         $db = $db->unlisten('foo');
357         $db = $db->unlisten('*');
358
359       Unsubscribe from a channel, "*" can be used to unsubscribe from all
360       channels.
361
362   update
363         my $results = $db->update($table, \%fieldvals, \%where, \%options);
364
365       Generate an "UPDATE" statement with "abstract" in Mojo::Pg (usually an
366       SQL::Abstract::Pg object) and execute it with "query". You can also
367       append a callback to perform operations non-blocking.
368
369         $db->update(some_table => {foo => 'baz'} => {foo => 'bar'} => sub ($db, $err, $results) {
370           ...
371         });
372         Mojo::IOLoop->start unless Mojo::IOLoop->is_running;
373
374       Use all the same argument variations you would pass to the "update"
375       method of SQL::Abstract.
376
377         # "UPDATE some_table SET foo = 'bar' WHERE id = 23"
378         $db->update('some_table', {foo => 'bar'}, {id => 23});
379
380         # "UPDATE some_table SET foo = {1,2,3} WHERE id = 23"
381         $db->update('some_table', {foo => [1, 2, 3]}, {id => 23});
382
383         # "UPDATE some_table SET foo = 'bar' WHERE foo LIKE '%test%'"
384         $db->update('some_table', {foo => 'bar'}, {foo => {-like => '%test%'}});
385
386         # "UPDATE some_table SET foo = 'bar' WHERE id = 23 RETURNING id"
387         $db->update('some_table', {foo => 'bar'}, {id => 23}, {returning => 'id'});
388
389         # "UPDATE some_table SET foo = '[1,2,3]' WHERE bar = 23"
390         $db->update('some_table', {foo => {-json => [1, 2, 3]}}, {bar => 23});
391
392   update_p
393         my $promise = $db->update_p($table, \%fieldvals, \%where, \%options);
394
395       Same as "update", but performs all operations non-blocking and returns
396       a Mojo::Promise object instead of accepting a callback.
397
398         $db->update_p(some_table => {foo => 'baz'} => {foo => 'bar'})->then(sub ($results) {
399           ...
400         })->catch(sub ($err) {
401           ...
402         })->wait;
403

NAME

SYNOPSIS

DESCRIPTION

EVENTS

ATTRIBUTES

METHODS

SEE ALSO