1DBSchema::Column(3) User Contributed Perl Documentation DBSchema::Column(3)
2
6 DBIx::DBSchema::Column - Column objects
7
9 use DBIx::DBSchema::Column;
10 #named params with a hashref (preferred)
12 $column = new DBIx::DBSchema::Column ( {
13 'name' => 'column_name',
14 'type' => 'varchar'
15 'null' => 'NOT NULL',
16 'length' => 64,
17 'default' => '',
18 'local' => '',
19 } );
20 #list
22 $column = new DBIx::DBSchema::Column ( $name, $sql_type, $nullability, $length, $default, $local );
23 $name = $column->name;
25 $column->name( 'name' );
26 $sql_type = $column->type;
28 $column->type( 'sql_type' );
29 $null = $column->null;
31 $column->null( 'NULL' );
32 $column->null( 'NOT NULL' );
33 $column->null( '' );
34 $length = $column->length;
36 $column->length( '10' );
37 $column->length( '8,2' );
38 $default = $column->default;
40 $column->default( 'Roo' );
41 $sql_line = $column->line;
43 $sql_line = $column->line($datasrc);
44 $sql_add_column = $column->sql_add_column;
46 $sql_add_column = $column->sql_add_column($datasrc);
47
49 DBIx::DBSchema::Column objects represent columns in tables (see
50 DBIx::DBSchema::Table).
51
53 new HASHREF
54 new [ name [ , type [ , null [ , length [ , default [ , local ] ] ] ]
55 ] ]
56 Creates a new DBIx::DBSchema::Column object. Takes a hashref of
57 named parameters, or a list. name is the name of the column. type
58 is the SQL data type. null is the nullability of the column
59 (intrepreted using Perl's rules for truth, with one exception: `NOT
60 NULL' is false). length is the SQL length of the column. default
61 is the default value of the column. local is reserved for
62 database-specific information.
63 Note: If you pass a scalar reference as the default rather than a
65 scalar value, it will be dereferenced and quoting will be forced
66 off. This can be used to pass SQL functions such as "now()" or
67 explicit empty strings as '' as defaults.
68 name [ NAME ]
70 Returns or sets the column name.
71 type [ TYPE ]
73 Returns or sets the column type.
74 null [ NULL ]
76 Returns or sets the column null flag (the empty string is
77 equivalent to `NOT NULL')
78 length [ LENGTH ]
80 Returns or sets the column length.
81 default [ LOCAL ]
83 Returns or sets the default value.
84 local [ LOCAL ]
86 Returns or sets the database-specific field.
87 table_obj [ TABLE_OBJ ]
89 Returns or sets the table object (see DBIx::DBSchema::Table).
90 Typically set internally when a column object is added to a table
91 object.
92 table_name
94 Returns the table name, or the empty string if this column has not
95 yet been assigned to a table.
96 line [ DATABASE_HANDLE | DATA_SOURCE [ USERNAME PASSWORD [ ATTR ] ] ]
98 Returns an SQL column definition.
99 The data source can be specified by passing an open DBI database
101 handle, or by passing the DBI data source name, username and
102 password.
103 Although the username and password are optional, it is best to call
105 this method with a database handle or data source including a valid
106 username and password - a DBI connection will be opened and the
107 quoting and type mapping will be more reliable.
108 If passed a DBI data source (or handle) such as
110 `DBI:mysql:database' or `DBI:Pg:dbname=database', will use syntax
111 specific to that database engine. Currently supported databases
112 are MySQL and PostgreSQL. Non-standard syntax for other engines
113 (if applicable) may also be supported in the future.
114 quoted_default DATABASE_HANDLE
116 Returns this column's default value quoted for the database.
117 sql_add_column [ DBH ]
119 Returns a list of SQL statements to add this column to an existing
120 table. (To create a new table, see "sql_create_table" in
121 DBIx::DBSchema::Table instead.)
122 The data source can be specified by passing an open DBI database
124 handle, or by passing the DBI data source name, username and
125 password.
126 Although the username and password are optional, it is best to call
128 this method with a database handle or data source including a valid
129 username and password - a DBI connection will be opened and the
130 quoting and type mapping will be more reliable.
131 If passed a DBI data source (or handle) such as
133 `DBI:Pg:dbname=database', will use PostgreSQL-specific syntax.
134 Non-standard syntax for other engines (if applicable) may also be
135 supported in the future.
136 sql_alter_column PROTOTYPE_COLUMN [ DATABASE_HANDLE | DATA_SOURCE [
138 USERNAME PASSWORD [ ATTR ] ] ]
139 Returns a list of SQL statements to alter this column so that it is
140 identical to the provided prototype column, also a
141 DBIx::DBSchema::Column object.
142 Optionally, the data source can be specified by passing an open DBI
144 database handle, or by passing the DBI data source name, username
145 and password.
146 If passed a DBI data source (or handle) such as
148 `DBI:Pg:dbname=database', will use PostgreSQL-specific syntax.
149 Non-standard syntax for other engines (if applicable) may also be
150 supported in the future.
151 If not passed a data source (or handle), or if there is no driver
153 for the specified database, will attempt to use generic SQL syntax.
154 sql_drop_column [ DBH ]
156 Returns a list of SQL statements to drop this column from an
157 existing table.
158 The optional database handle or DBI data source/username/password
160 is not yet used.
161
163 Ivan Kohler <ivan-dbix-dbschema@420.am>
164
166 Copyright (c) 2000-2006 Ivan Kohler Copyright (c) 2007-2010 Freeside
167 Internet Services, Inc. All rights reserved. This program is free
168 software; you can redistribute it and/or modify it under the same terms
169 as Perl itself.
170
172 The new() method should warn that "Old-style $class creation without
173 named parameters is deprecated!"
174 Better documentation is needed for sql_add_column
176 sql_alter_column() has database-specific foo that should be abstracted
178 info DBIx::DBSchema::DBD::Pg
179 nullify_default option should be documented
181
183 DBIx::DBSchema::Table, DBIx::DBSchema, DBIx::DBSchema::DBD, DBI
184perl v5.12.1 2010-03-27 DBSchema::Column(3)