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')
13           ->hashes->map(sub { $_->{bar} })->join("\n")->say;
14

DESCRIPTION

16       Mojo::Pg::Database is a container for DBD::Pg database handles used by
17       Mojo::Pg.
18

EVENTS

20       Mojo::Pg::Database inherits all events from Mojo::EventEmitter and can
21       emit the following new ones.
22
23   close
24         $db->on(close => sub {
25           my $db = shift;
26           ...
27         });
28
29       Emitted when the database connection gets closed while waiting for
30       notifications.
31
32   notification
33         $db->on(notification => sub {
34           my ($db, $name, $pid, $payload) = @_;
35           ...
36         });
37
38       Emitted when a notification has been received.
39

ATTRIBUTES

41       Mojo::Pg::Database implements the following attributes.
42
43   dbh
44         my $dbh = $db->dbh;
45         $db     = $db->dbh($dbh);
46
47       DBD::Pg database handle used for all queries.
48
49         # Use DBI utility methods
50         my $quoted = $db->dbh->quote_identifier('foo.bar');
51
52   pg
53         my $pg = $db->pg;
54         $db    = $db->pg(Mojo::Pg->new);
55
56       Mojo::Pg object this database belongs to. Note that this attribute is
57       weakened.
58
59   results_class
60         my $class = $db->results_class;
61         $db       = $db->results_class('MyApp::Results');
62
63       Class to be used by "query", defaults to Mojo::Pg::Results. Note that
64       this class needs to have already been loaded before "query" is called.
65

METHODS

67       Mojo::Pg::Database inherits all methods from Mojo::EventEmitter and
68       implements the following new ones.
69
70   begin
71         my $tx = $db->begin;
72
73       Begin transaction and return Mojo::Pg::Transaction object, which will
74       automatically roll back the transaction unless "commit" in
75       Mojo::Pg::Transaction has been called before it is destroyed.
76
77         # Insert rows in a transaction
78         eval {
79           my $tx = $db->begin;
80           $db->insert('frameworks', {name => 'Catalyst'});
81           $db->insert('frameworks', {name => 'Mojolicious'});
82           $tx->commit;
83         };
84         say $@ if $@;
85
86   delete
87         my $results = $db->delete($table, \%where, \%options);
88
89       Generate a "DELETE" statement with "abstract" in Mojo::Pg (usually an
90       SQL::Abstract::Pg object) and execute it with "query". You can also
91       append a callback to perform operations non-blocking.
92
93         $db->delete(some_table => sub {
94           my ($db, $err, $results) = @_;
95           ...
96         });
97         Mojo::IOLoop->start unless Mojo::IOLoop->is_running;
98
99       Use all the same argument variations you would pass to the "delete"
100       method of SQL::Abstract.
101
102         # "delete from some_table"
103         $db->delete('some_table');
104
105         # "delete from some_table where foo = 'bar'"
106         $db->delete('some_table', {foo => 'bar'});
107
108         # "delete from some_table where foo like '%test%'"
109         $db->delete('some_table', {foo => {-like => '%test%'}});
110
111         # "delete from some_table where foo = 'bar' returning id"
112         $db->delete('some_table', {foo => 'bar'}, {returning => 'id'});
113
114   delete_p
115         my $promise = $db->delete_p($table, \%where, \%options);
116
117       Same as "delete", but performs all operations non-blocking and returns
118       a Mojo::Promise object instead of accepting a callback.
119
120         $db->delete_p('some_table')->then(sub {
121           my $results = shift;
122           ...
123         })->catch(sub {
124           my $err = shift;
125           ...
126         })->wait;
127
128   disconnect
129         $db->disconnect;
130
131       Disconnect "dbh" and prevent it from getting reused.
132
133   dollar_only
134         $db = $db->dollar_only;
135
136       Activate "pg_placeholder_dollaronly" for next "query" call and allow
137       "?"  to be used as an operator.
138
139         # Check for a key in a JSON document
140         $db->dollar_only->query('select * from foo where bar ? $1', 'baz')
141           ->expand->hashes->map(sub { $_->{bar}{baz} })->join("\n")->say;
142
143   insert
144         my $results = $db->insert($table, \@values || \%fieldvals, \%options);
145
146       Generate an "INSERT" statement with "abstract" in Mojo::Pg (usually an
147       SQL::Abstract::Pg object) and execute it with "query". You can also
148       append a callback to perform operations non-blocking.
149
150         $db->insert(some_table => {foo => 'bar'} => sub {
151           my ($db, $err, $results) = @_;
152           ...
153         });
154         Mojo::IOLoop->start unless Mojo::IOLoop->is_running;
155
156       Use all the same argument variations you would pass to the "insert"
157       method of SQL::Abstract.
158
159         # "insert into some_table (foo, baz) values ('bar', 'yada')"
160         $db->insert('some_table', {foo => 'bar', baz => 'yada'});
161
162         # "insert into some_table (foo) values ({1,2,3})"
163         $db->insert('some_table', {foo => [1, 2, 3]});
164
165         # "insert into some_table (foo) values ('bar') returning id"
166         $db->insert('some_table', {foo => 'bar'}, {returning => 'id'});
167
168         # "insert into some_table (foo) values ('bar') returning id, foo"
169         $db->insert('some_table', {foo => 'bar'}, {returning => ['id', 'foo']});
170
171       As well as some PostgreSQL specific extensions added by
172       SQL::Abstract::Pg.
173
174         # "insert into some_table (foo) values ('bar') on conflict do nothing"
175         $db->insert('some_table', {foo => 'bar'}, {on_conflict => undef});
176
177       Including operations commonly referred to as "upsert".
178
179         # "insert into t (a) values ('b') on conflict (a) do update set a = 'c'"
180         $db->insert('t', {a => 'b'}, {on_conflict => [a => {a => 'c'}]});
181
182         # "insert into t (a, b) values ('c', 'd')
183         #  on conflict (a, b) do update set a = 'e'"
184         $db->insert(
185           't', {a => 'c', b => 'd'}, {on_conflict => [['a', 'b'] => {a => 'e'}]});
186
187   insert_p
188         my $promise = $db->insert_p($table, \@values || \%fieldvals, \%options);
189
190       Same as "insert", but performs all operations non-blocking and returns
191       a Mojo::Promise object instead of accepting a callback.
192
193         $db->insert_p(some_table => {foo => 'bar'})->then(sub {
194           my $results = shift;
195           ...
196         })->catch(sub {
197           my $err = shift;
198           ...
199         })->wait;
200
201   is_listening
202         my $bool = $db->is_listening;
203
204       Check if "dbh" is listening for notifications.
205
206   listen
207         $db = $db->listen('foo');
208
209       Subscribe to a channel and receive "notification" events when the
210       Mojo::IOLoop event loop is running.
211
212   notify
213         $db = $db->notify('foo');
214         $db = $db->notify(foo => 'bar');
215
216       Notify a channel.
217
218   pid
219         my $pid = $db->pid;
220
221       Return the process id of the backend server process.
222
223   ping
224         my $bool = $db->ping;
225
226       Check database connection.
227
228   query
229         my $results = $db->query('select * from foo');
230         my $results = $db->query('insert into foo values (?, ?, ?)', @values);
231         my $results = $db->query('select ?::json as foo', {json => {bar => 'baz'}});
232
233       Execute a blocking SQL
234       <http://www.postgresql.org/docs/current/static/sql.html> statement and
235       return a results object based on "results_class" (which is usually
236       Mojo::Pg::Results) with the query results. The DBD::Pg statement handle
237       will be automatically reused when it is not active anymore, to increase
238       the performance of future queries. You can also append a callback to
239       perform operations non-blocking.
240
241         $db->query('insert into foo values (?, ?, ?)' => @values => sub {
242           my ($db, $err, $results) = @_;
243           ...
244         });
245         Mojo::IOLoop->start unless Mojo::IOLoop->is_running;
246
247       Hash reference arguments containing a value named "json", will be
248       encoded to JSON text with "to_json" in Mojo::JSON. To accomplish the
249       reverse, you can use the method "expand" in Mojo::Pg::Results, which
250       automatically decodes all fields of the types "json" and "jsonb" with
251       "from_json" in Mojo::JSON to Perl values.
252
253         # "I ♥ Mojolicious!"
254         $db->query('select ?::jsonb as foo', {json => {bar => 'I ♥ Mojolicious!'}})
255           ->expand->hash->{foo}{bar};
256
257       Hash reference arguments containing values named "type" and "value",
258       can be used to bind specific DBD::Pg data types to placeholders.
259
260         # Insert binary data
261         use DBD::Pg ':pg_types';
262         $db->query('insert into bar values (?)', {type => PG_BYTEA, value => $bytes});
263
264   query_p
265         my $promise = $db->query_p('select * from foo');
266
267       Same as "query", but performs all operations non-blocking and returns a
268       Mojo::Promise object instead of accepting a callback.
269
270         $db->query_p('insert into foo values (?, ?, ?)' => @values)->then(sub {
271           my $results = shift;
272           ...
273         })->catch(sub {
274           my $err = shift;
275           ...
276         })->wait;
277
278   select
279         my $results = $db->select($source, $fields, $where, \%options);
280
281       Generate a "SELECT" statement with "abstract" in Mojo::Pg (usually an
282       SQL::Abstract::Pg object) and execute it with "query". You can also
283       append a callback to perform operations non-blocking.
284
285         $db->select(some_table => ['foo'] => {bar => 'yada'} => sub {
286           my ($db, $err, $results) = @_;
287           ...
288         });
289         Mojo::IOLoop->start unless Mojo::IOLoop->is_running;
290
291       Use all the same argument variations you would pass to the "select"
292       method of SQL::Abstract.
293
294         # "select * from some_table"
295         $db->select('some_table');
296
297         # "select id, foo from some_table"
298         $db->select('some_table', ['id', 'foo']);
299
300         # "select * from some_table where foo = 'bar'"
301         $db->select('some_table', undef, {foo => 'bar'});
302
303         # "select * from some_table where foo like '%test%'"
304         $db->select('some_table', undef, {foo => {-like => '%test%'}});
305
306       As well as some PostgreSQL specific extensions added by
307       SQL::Abstract::Pg.
308
309         # "select * from foo join bar on (bar.foo_id = foo.id)"
310         $db->select(['foo', ['bar', foo_id => 'id']]);
311
312         # "select * from foo left join bar on (bar.foo_id = foo.id)"
313         $db->select(['foo', [-left => 'bar', foo_id => 'id']]);
314
315         # "select foo as bar from some_table"
316         $db->select('some_table', [[foo => 'bar']]);
317
318         # "select * from some_table where foo = '[1,2,3]'"
319         $db->select('some_table', '*', {foo => {'=' => {-json => [1, 2, 3]}}});
320
321         # "select extract(epoch from foo) as foo, bar from some_table"
322         $db->select('some_table', [\'extract(epoch from foo) as foo', 'bar']);
323
324         # "select 'test' as foo, bar from some_table"
325         $db->select('some_table', [\['? as foo', 'test'], 'bar']);
326
327       Including a new last argument to pass many new options.
328
329         # "select * from some_table where foo = 'bar' order by id desc"
330         $db->select('some_table', '*', {foo => 'bar'}, {order_by => {-desc => 'id'}});
331
332         # "select * from some_table limit 10 offset 20"
333         $db->select('some_table', '*', undef, {limit => 10, offset => 20});
334
335         # "select * from some_table where foo = 23 group by foo, bar"
336         $db->select('some_table', '*', {foo => 23}, {group_by => ['foo', 'bar']});
337
338         # "select * from t where a = 'b' group by c having d = 'e'"
339         $db->select('t', '*', {a => 'b'}, {group_by => ['c'], having => {d => 'e'}});
340
341         # "select * from some_table where id = 1 for update"
342         $db->select('some_table', '*', {id => 1}, {for => 'update'});
343
344         # "select * from some_table where id = 1 for update skip locked"
345         $db->select('some_table', '*', {id => 1}, {for => \'update skip locked'});
346
347   select_p
348         my $promise = $db->select_p($source, $fields, $where, \%options);
349
350       Same as "select", but performs all operations non-blocking and returns
351       a Mojo::Promise object instead of accepting a callback.
352
353         $db->select_p(some_table => ['foo'] => {bar => 'yada'})->then(sub {
354           my $results = shift;
355           ...
356         })->catch(sub {
357           my $err = shift;
358           ...
359         })->wait;
360
361   tables
362         my $tables = $db->tables;
363
364       Return table and view names for this database, that are visible to the
365       current user and not internal, as an array reference.
366
367         # Names of all tables
368         say for @{$db->tables};
369
370   unlisten
371         $db = $db->unlisten('foo');
372         $db = $db->unlisten('*');
373
374       Unsubscribe from a channel, "*" can be used to unsubscribe from all
375       channels.
376
377   update
378         my $results = $db->update($table, \%fieldvals, \%where, \%options);
379
380       Generate an "UPDATE" statement with "abstract" in Mojo::Pg (usually an
381       SQL::Abstract::Pg object) and execute it with "query". You can also
382       append a callback to perform operations non-blocking.
383
384         $db->update(some_table => {foo => 'baz'} => {foo => 'bar'} => sub {
385           my ($db, $err, $results) = @_;
386           ...
387         });
388         Mojo::IOLoop->start unless Mojo::IOLoop->is_running;
389
390       Use all the same argument variations you would pass to the "update"
391       method of SQL::Abstract.
392
393         # "update some_table set foo = 'bar' where id = 23"
394         $db->update('some_table', {foo => 'bar'}, {id => 23});
395
396         # "update some_table set foo = {1,2,3} where id = 23"
397         $db->update('some_table', {foo => [1, 2, 3]}, {id => 23});
398
399         # "update some_table set foo = 'bar' where foo like '%test%'"
400         $db->update('some_table', {foo => 'bar'}, {foo => {-like => '%test%'}});
401
402         # "update some_table set foo = 'bar' where id = 23 returning id"
403         $db->update('some_table', {foo => 'bar'}, {id => 23}, {returning => 'id'});
404
405         # "update some_table set foo = '[1,2,3]' where bar = 23"
406         $db->update('some_table', {foo => {-json => [1, 2, 3]}}, {bar => 23});
407
408   update_p
409         my $promise = $db->update_p($table, \%fieldvals, \%where, \%options);
410
411       Same as "update", but performs all operations non-blocking and returns
412       a Mojo::Promise object instead of accepting a callback.
413
414         $db->update_p(some_table => {foo => 'baz'} => {foo => 'bar'})->then(sub {
415           my $results = shift;
416           ...
417         })->catch(sub {
418           my $err = shift;
419           ...
420         })->wait;
421

NAME

SYNOPSIS

DESCRIPTION

EVENTS

ATTRIBUTES

METHODS

SEE ALSO