1Padre::DB::Snippets(3)User Contributed Perl DocumentationPadre::DB::Snippets(3)
2
6 Padre::DB::Snippets - Padre::DB class for the snippets table
7
9 TO BE COMPLETED
10
12 base
13 # Returns 'Padre::DB'
14 my $namespace = Padre::DB::Snippets->base;
15 Normally you will only need to work directly with a table class, and
17 only with one ORLite package.
18 However, if for some reason you need to work with multiple ORLite
20 packages at the same time without hardcoding the root namespace all the
21 time, you can determine the root namespace from an object or table
22 class with the "base" method.
23 table
25 # Returns 'snippets'
26 print Padre::DB::Snippets->table;
27 While you should not need the name of table for any simple operations,
29 from time to time you may need it programatically. If you do need it,
30 you can use the "table" method to get the table name.
31 load
33 my $object = Padre::DB::Snippets->load( $id );
34 If your table has single column primary key, a "load" method will be
36 generated in the class. If there is no primary key, the method is not
37 created.
38 The "load" method provides a shortcut mechanism for fetching a single
40 object based on the value of the primary key. However it should only be
41 used for cases where your code trusts the record to already exists.
42 It returns a "Padre::DB::Snippets" object, or throws an exception if
44 the object does not exist.
45 select
47 # Get all objects in list context
48 my @list = Padre::DB::Snippets->select;
49 # Get a subset of objects in scalar context
51 my $array_ref = Padre::DB::Snippets->select(
52 'where id > ? order by id',
53 1000,
54 );
55 The "select" method executes a typical SQL "SELECT" query on the
57 snippets table.
58 It takes an optional argument of a SQL phrase to be added after the
60 "FROM snippets" section of the query, followed by variables to be bound
61 to the placeholders in the SQL phrase. Any SQL that is compatible with
62 SQLite can be used in the parameter.
63 Returns a list of Padre::DB::Snippets objects when called in list
65 context, or a reference to an "ARRAY" of Padre::DB::Snippets objects
66 when called in scalar context.
67 Throws an exception on error, typically directly from the DBI layer.
69 iterate
71 Padre::DB::Snippets->iterate( sub {
72 print $_->id . "\n";
73 } );
74 The "iterate" method enables the processing of large tables one record
76 at a time without loading having to them all into memory in advance.
77 This plays well to the strength of SQLite, allowing it to do the work
79 of loading arbitrarily large stream of records from disk while
80 retaining the full power of Perl when processing the records.
81 The last argument to "iterate" must be a subroutine reference that will
83 be called for each element in the list, with the object provided in the
84 topic variable $_.
85 This makes the "iterate" code fragment above functionally equivalent to
87 the following, except with an O(1) memory cost instead of O(n).
88 foreach ( Padre::DB::Snippets->select ) {
90 print $_->id . "\n";
91 }
92 You can filter the list via SQL in the same way you can with "select".
94 Padre::DB::Snippets->iterate(
96 'order by ?', 'id',
97 sub {
98 print $_->id . "\n";
99 }
100 );
101 You can also use it in raw form from the root namespace for better
103 control. Using this form also allows for the use of arbitrarily
104 complex queries, including joins. Instead of being objects, rows are
105 provided as "ARRAY" references when used in this form.
106 Padre::DB->iterate(
108 'select name from snippets order by id',
109 sub {
110 print $_->[0] . "\n";
111 }
112 );
113 count
115 # How many objects are in the table
116 my $rows = Padre::DB::Snippets->count;
117 # How many objects
119 my $small = Padre::DB::Snippets->count(
120 'where id > ?',
121 1000,
122 );
123 The "count" method executes a "SELECT COUNT(*)" query on the snippets
125 table.
126 It takes an optional argument of a SQL phrase to be added after the
128 "FROM snippets" section of the query, followed by variables to be bound
129 to the placeholders in the SQL phrase. Any SQL that is compatible with
130 SQLite can be used in the parameter.
131 Returns the number of objects that match the condition.
133 Throws an exception on error, typically directly from the DBI layer.
135 new
137 TO BE COMPLETED
138 The "new" constructor is used to create a new abstract object that is
140 not (yet) written to the database.
141 Returns a new Padre::DB::Snippets object.
143 create
145 my $object = Padre::DB::Snippets->create(
146 id => 'value',
148 mimetype => 'value',
150 category => 'value',
152 name => 'value',
154 snippet => 'value',
156 );
158 The "create" constructor is a one-step combination of "new" and
160 "insert" that takes the column parameters, creates a new
161 Padre::DB::Snippets object, inserts the appropriate row into the
162 snippets table, and then returns the object.
163 If the primary key column "id" is not provided to the constructor (or
165 it is false) the object returned will have "id" set to the new unique
166 identifier.
167 Returns a new snippets object, or throws an exception on error,
169 typically from the DBI layer.
170 insert
172 $object->insert;
173 The "insert" method commits a new object (created with the "new"
175 method) into the database.
176 If a the primary key column "id" is not provided to the constructor (or
178 it is false) the object returned will have "id" set to the new unique
179 identifier.
180 Returns the object itself as a convenience, or throws an exception on
182 error, typically from the DBI layer.
183 delete
185 # Delete a single instantiated object
186 $object->delete;
187 # Delete multiple rows from the snippets table
189 Padre::DB::Snippets->delete('where id > ?', 1000);
190 The "delete" method can be used in a class form and an instance form.
192 When used on an existing Padre::DB::Snippets instance, the "delete"
194 method removes that specific instance from the "snippets", leaving the
195 object intact for you to deal with post-delete actions as you wish.
196 When used as a class method, it takes a compulsory argument of a SQL
198 phrase to be added after the "DELETE FROM snippets" section of the
199 query, followed by variables to be bound to the placeholders in the SQL
200 phrase. Any SQL that is compatible with SQLite can be used in the
201 parameter.
202 Returns true on success or throws an exception on error, or if you
204 attempt to call delete without a SQL condition phrase.
205 truncate
207 # Delete all records in the snippets table
208 Padre::DB::Snippets->truncate;
209 To prevent the common and extremely dangerous error case where deletion
211 is called accidentally without providing a condition, the use of the
212 "delete" method without a specific condition is forbidden.
213 Instead, the distinct method "truncate" is provided to delete all
215 records in a table with specific intent.
216 Returns true, or throws an exception on error.
218
220 id
221 if ( $object->id ) {
222 print "Object has been inserted\n";
223 } else {
224 print "Object has not been inserted\n";
225 }
226 Returns true, or throws an exception on error.
228 REMAINING ACCESSORS TO BE COMPLETED
230
232 The snippets table was originally created with the following SQL
233 command.
234 CREATE TABLE snippets (
236 id INTEGER PRIMARY KEY,
237 mimetype VARCHAR(255),
238 category VARCHAR(255),
239 name VARCHAR(255),
240 snippet TEXT
241 )
242
244 Padre::DB::Snippets is part of the Padre::DB API.
245 See the documentation for Padre::DB for more information.
247
249 Adam Kennedy <adamk@cpan.org>
250
252 Copyright 2010 Adam Kennedy.
253 This program is free software; you can redistribute it and/or modify it
255 under the same terms as Perl itself.
256 The full text of the license can be found in the LICENSE file included
258 with this module.
259perl v5.30.1 2020-01-30 Padre::DB::Snippets(3)