NAME
DBIx::Wrapper - A wrapper around the DBI
SYNOPSIS
use DBIx::Wrapper;
my $db = DBIx::Wrapper->connect($dsn, $user, $auth, \%attr);
my $db = DBIx::Wrapper->connect($dsn, $user, $auth, \%attr,
{ error_handler => sub { print $DBI::errstr },
debug_handler => sub { print $DBI::errstr },
});
my $dbi_obj = DBI->connect(...)
my $db = DBIx::Wrapper->newFromDBI($dbi_obj);
my $dbi_obj = $db->getDBI;
my $rv = $db->insert($table, { id => 5, val => "myval",
the_date => \"NOW()",
});
my $rv = $db->insert($table, { id => 5, val => "myval",
the_date => $db->command("NOW()"),
});
my $rv = $db->replace($table, \%data);
my $rv = $db->smartReplace($table, \%data)
my $rv = $db->delete($table, \%keys);
my $rv = $db->update($table, \%keys, \%data);
my $rv = $db->smartUpdate($table, \%keys, \%data);
my $row = $db->selectFromHash($table, \%keys, \@cols);
my $row = $db->selectFromHashMulti($table, \%keys, \@cols);
my $val = $db->selectValueFromHash($table, \%keys, $col);
my $vals = $db->selectValueFromHashMulti($table, \%keys, \@cols);
my $row = $db->nativeSelect($query, \@exec_args);
my $loop = $db->nativeSelectExecLoop($query);
foreach my $val (@vals) {
my $row = $loop->next([ $val ]);
}
my $row = $db->nativeSelectWithArrayRef($query, \@exec_args);
my $rows = $db->nativeSelectMulti($query, \@exec_args);
my $loop = $db->nativeSelectMultiExecLoop($query)
foreach my $val (@vals) {
my $rows = $loop->next([ $val ]);
}
my $rows = $db->nativeSelectMultiWithArrayRef($query, \@exec_args);
my $hash = $db->nativeSelectMapping($query, \@exec_args);
my $hash = $db->nativeSelectDynaMapping($query, \@cols, \@exec_args);
my $hash = $db->nativeSelectRecordMapping($query, \@exec_args);
my $hash = $db->nativeSelectRecordDynaMapping($query, $col, \@exec_args);
my $val = $db->nativeSelectValue($query, \@exec_args);
my $vals = $db->nativeSelectValuesArray($query, \@exec_args);
my $row = $db->abstractSelect($table, \@fields, \%where, \@order);
my $rows = $db->abstractSelectMulti($table, \@fields, \%where, \@order);
my $loop = $db->nativeSelectLoop($query, @exec_args);
while (my $row = $loop->next) {
my $id = $$row{id};
}
my $rv = $db->nativeQuery($query, @exec_args);
my $loop = $db->nativeQueryLoop("UPDATE my_table SET value=? WHERE id=?");
$loop->next([ 'one', 1]);
$loop->next([ 'two', 2]);
my $id = $db->getLastInsertId;
$db->debugOn(\*FILE_HANDLE);
$db->setNameArg($arg)
$db->commit();
$db->ping();
$db->err();Attributes
Attributes accessed in DBIx::Wrapper object via hash access are
passed on or retrieved from the underlying DBI object, e.g.,
$dbi_obj->{RaiseError} = 1Named Placeholders
All native* methods (except for nativeSelectExecLoop) support
named placeholders. That is, instead of using ? as a
placeholder, you can use :name, where name is the name of a key
in the hash passed to the method. To use named placeholders,
pass a hash reference containing the values in place of the
@exec_args argument. E.g.,
my $row = $db->nativeSelect("SELECT * FROM test_table WHERE id=:id", { id => 1 });
:: in the query string gets converted to : so you can include
literal colons in the query. :"var name" and :'var name' are
also supported so you can use variable names containing spaces.
The implementation uses ? as placeholders under the hood so that
quoting is done properly. So if your database driver does not
support placeholders, named placeholders will not help you.DESCRIPTION
DBIx::Wrapper provides a wrapper around the DBI that makes it a bit easier on the programmer. This module allows you to execute a query with a single method call as well as make inserts easier, etc. It also supports running hooks at various stages of processing a query (see the section on Hooks).
METHODS
connect($data_source, $username, $auth, \%attr, \%params)
Connects to the given database. The first four parameters are the same parameters you would pass to the connect call when using DBI directly.
The %params hash is optional and contains extra parameters to control the behaviour of DBIx::Wrapper itself. Following are the valid parameters.
- error_handler and debug_handler
-
These values should either be a reference to a subroutine, or a reference to an array whose first element is an object and whose second element is a method name to call on that object. The parameters passed to the error_handler callback are the current DBIx::Wrapper object and an error string, usually the query if appropriate. The parameters passed to the debug_handler callback are the current DBIx::Wrapper object, an error string, and the filehandle passed to the debugOn() method (defaults to STDERR). E.g.,
sub do_error { my ($db, $str) = @_; print $DBI::errstr; } sub do_debug { my ($db, $str, $fh) = @_; print $fh "query was: $str\n"; } my $db = DBIx::Wrapper->connect($ds, $un, $auth, \%attr, { error_handler => \&do_error, debug_handler => \&do_debug, }); - db_style
-
Used to control some database specific logic. The default value is 'mysql'. Currently, this is only used for the getLastInsertId() method. MSSQL is supported with a value of mssql for this parameter.
- heavy
-
If set to a true value, any hashes returned will actually be objects on which you can call methods to get the values back. E.g.,
my $row = $db->nativeSelect($query); my $id = $row->id; or my $id = $row->{id};
new($data_source, $username, $auth, \%attr, \%params)
An alias for connect().
reconnect()
Reconnect to the database using the same parameters that were given to the connect() method. It does not try to disconnect before attempting to connect again.
disconnect()
Disconnect from the database. This disconnects and frees up the underlying DBI object.
connect_one(\@cfg_list, \%attr)
Connects to a random database out of the list. This is useful
for connecting to a slave database out of a group for read-only
access. Ths list should look similar to the following:
my $cfg_list = [ { driver => 'mysql',
host => 'db0.example.com',
port => 3306,
database => 'MyDB',
user => 'dbuser',
auth => 'dbpwd',
attr => { RaiseError => 1 },
weight => 1,
},
{ driver => 'mysql',
host => 'db1.example.com',
port => 3306,
database => 'MyDB',
user => 'dbuser',
auth => 'dbpwd',
attr => { RaiseError => 1 },
weight => 2,
},
];
where the weight fields are optional (defaulting to 1). The
attr field is also optional and corresponds to the 4th argument
to DBI's connect() method. The \%attr passed to this method is
an optional parameter specifying the defaults for \%attr to be
passed to the connect() method. The attr field in the config
for each database in the list overrides any in the \%attr
parameter passed into the method.
You may also pass the DSN string for the connect() method as the
'dsn' field in each config instead of the separate driver, host,
port, and database fields, e.g.,
my $cfg_list = [ { dsn => 'dbi:mysql:host=db0.example.com;database=MyDB;port=3306',
user => 'dbuser',
auth => 'dbpwd',
attr => { RaiseError => 1 },
weight => 1,
},
];newFromDBI($dbh)
Returns a new DBIx::Wrapper object from a DBI object that has already been created. Note that when created this way, disconnect() will not be called automatically on the underlying DBI object when the DBIx::Wrapper object goes out of scope.
getDBI()
Return the underlying DBI object used to query the database.
insert($table, \%data)
Insert the provided row into the database. $table is the name of the table you want to insert into. %data is the data you want to insert -- a hash with key/value pairs representing a row to be insert into the database.
replace($table, \%data)
Same as insert(), except does a REPLACE instead of an INSERT for databases which support it.
smartReplace($table, \%data)
This method is MySQL specific. If $table has an auto_increment
column, the return value will be the value of the auto_increment
column. So if that column was specified in \%data, that value
will be returned, otherwise, an insert will be performed and the
value of LAST_INSERT_ID() will be returned. If there is no
auto_increment column, but primary keys are provided, the row
containing the primary keys will be returned. Otherwise, a true
value will be returned upon success.delete($table, \%keys), delete($table, \@keys)
Delete rows from table $table using the key/value pairs in %keys
to specify the WHERE clause of the query. Multiple key/value
pairs are joined with 'AND' in the WHERE clause. The cols
parameter can optionally be an array ref instead of a hashref.
E.g.
$db->delete($table, [ key1 => $val1, key2 => $val2 ])
This is so that the order of the parameters in the WHERE clause
are kept in the same order. This is required to use the correct
multi field indexes in some databases.update($table, \%keys, \%data), update($table, \@keys, \%data)
Update the table using the key/value pairs in %keys to specify
the WHERE clause of the query. %data contains the new values
for the row(s) in the database. The keys parameter can
optionally be an array ref instead of a hashref. E.g.,
$db->update($table, [ key1 => $val1, key2 => $val2 ], \%data);
This is so that the order of the parameters in the WHERE clause
are kept in the same order. This is required to use the correct
multi field indexes in some databases.selectFromHash($table, \%keys, \@cols);
Select from table $table using the key/value pairs in %keys to
specify the WHERE clause of the query. Multiple key/value pairs
are joined with 'AND' in the WHERE clause. Returns a single row
as a hashref. If %keys is empty or not passed, it is treated as
"SELECT * FROM $table" with no WHERE clause. @cols is a list of
columns you want back. If nothing is passed in @cols, all
columns will be returned.
If a value in the %keys hash is an array ref, the resulting
query will search for records with any of those values. E.g.,
my $row = $db->selectFromHash('the_table', { id => [ 5, 6, 7 ] });
will result in a query like
SELECT * FROM the_table WHERE (id=5 OR id=6 OR id=7)
The call
my $row = $db->selectFromHash('the_table', { id => [ 5, 6, 7 ], the_val => 'ten' });
will result in a query like
SELECT * FROM the_table WHERE (id=5 OR id=6 OR id=7) AND the_val="ten"
or, if a value was passed in for \@cols, e.g.,
my $row = $db->selectFromHash('the_table', { id => [ 5, 6, 7 ], the_val => 'ten' }, [ 'id' ]);
the resulting query would be
SELECT id FROM the_table WHERE (id=5 OR id=6 OR id=7) AND the_val="ten"selectFromHashMulti($table, \%keys, \@cols)
Like selectFromHash(), but returns all rows in the result.
Returns a reference to an array of hashrefs.selectValueFromHash($table, \%keys, $col)
Combination of nativeSelectValue() and selectFromHash().
Returns the first column from the result of a query given by
$table and %keys, as in selectFromHash(). $col is the column to
return.selectValueFromHashMulti($table, \%keys, \@cols)
Like selectValueFromhash(), but returns the first column of all
rows in the result.smartUpdate($table, \%keys, \%data)
Same as update(), except that a check is first made to see if there are any rows matching the data in %keys. If so, update() is called, otherwise, insert() is called.
nativeSelect($query, \@exec_args)
Executes the query in $query and returns a single row result (as a hash ref). If there are multiple rows in the result, the rest get silently dropped. @exec_args are the same arguments you would pass to an execute() called on a DBI object. Returns undef on error.
nativeSelectExecLoop($query)
Like nativeSelect(), but returns a loop object that can be used
to execute the same query over and over with different bind
parameters. This does a single DBI prepare() instead of a new
prepare() for select.
E.g.,
my $loop = $db->nativeSelectExecLoop("SELECT * FROM mytable WHERE id=?");
foreach my $id (@ids) {
my $row = $loop->next([ $id ]);
}nativeSelectWithArrayRef($query, \@exec_args)
Like nativeSelect(), but return a reference to an array instead
of a hash. Returns undef on error. If there are no results
from the query, a reference to an empty array is returned.nativeSelectMulti($query, \@exec_args)
Executes the query in $query and returns an array of rows, where
each row is a hash representing a row of the result. Returns
undef on error. If there are no results for the query, an empty
array ref is returned.nativeSelectMultiExecLoop($query)
Like nativeSelectExecLoop(), but returns an array of rows, where
each row is a hash representing a row of the result.nativeSelectMultiWithArrayRef($query, \@exec_args)
Like nativeSelectMulti(), but return a reference to an array of
arrays instead of to an array of hashes. Returns undef on error.nativeSelectMapping($query, \@exec_args)
Executes the given query and returns a reference to a hash
containing the first and second columns of the results as
key/value pairs.nativeSelectDynaMapping($query, \@cols, \@exec_args)
Similar to nativeSelectMapping() except you specify which
columns to use for the key/value pairs in the return hash. If
the first element of @cols starts with a digit, then @cols is
assumed to contain indexes for the two columns you wish to use.
Otherwise, @cols is assumed to contain the field names for the
two columns you wish to use.
For example,
nativeSelectMapping($query, \@exec_args) is
equivalent (and in fact calls) to
nativeSelectDynaMapping($query, [ 0, 1 ], $exec_args).nativeSelectRecordMapping($query, \@exec_args)
Similar to nativeSelectMapping(), except the values in the hash
are references to the corresponding record (as a hash).nativeSelectRecordDynaMapping($query, $col, \@exec_args)
Similar to nativeSelectRecordMapping(), except you specify
which column is the key in each key/value pair in the hash. If
$col starts with a digit, then it is assumed to contain the
index for the column you wish to use. Otherwise, $col is
assumed to contain the field name for the two columns you wish
to use.nativeSelectValue($query, \@exec_args)
Returns a single value, the first column from the first row of
the result. Returns undef on error or if there are no rows in
the result. Note this may be the same value returned for a NULL
value in the result.nativeSelectValuesArray($query, \@exec_args)
Like nativeSelectValue(), but return multiple values, e.g.,
return an array of ids for the query "SELECT id FROM WHERE
color_pref='red'".abstractSelect($table, \@fields, \%where, \@order)
Same as nativeSelect() except uses SQL::Abstract to generate the SQL. See the POD for SQL::Abstract for usage. You must have SQL::Abstract installed for this method to work.
abstractSelectMulti($table, \@fields, \%where, \@order)
Same as nativeSelectMulti() except uses SQL::Abstract to generate the SQL. See the POD for SQL::Abstract for usage. You must have SQL::Abstract installed for this method to work.
nativeSelectLoop($query, @exec_args)
Executes the query in $query, then returns an object that allows you to loop through one result at a time, e.g.,
my $loop = $db->nativeSelectLoop("SELECT * FROM my_table");
while (my $row = $loop->next) {
my $id = $$row{id};
}
To get the number of rows selected, you can call the
rowCountCurrent() method on the loop object, e.g.,
my $loop = $db->nativeSelectLoop("SELECT * FROM my_table");
my $rows_in_result = $loop->rowCountCurrent;
The count() method is an alias for rowCountCurrent().
To get the number of rows returned by next() so far, use the
rowCountTotal() method.nativeQuery($query, @exec_args)
Executes the query in $query and returns true if successful. This is typically used for deletes and is a catchall for anything the methods provided by this module don't take into account.
nativeQueryLoop($query)
A loop on nativeQuery, where any placeholders you have put in your query are bound each time you call next(). E.g.,
my $loop = $db->nativeQueryLoop("UPDATE my_table SET value=? WHERE id=?");
$loop->next([ 'one', 1]);
$loop->next([ 'two', 2]);newCommand($cmd)
This method is deprecated. Use $db->command($cmd_str) instead.
This creates a literal SQL command for use in insert(), update(), and related methods, since if you simply put something like "CUR_DATE()" as a value in the %data parameter passed to insert, the function will get quoted, and so will not work as expected. Instead, do something like this:
my $data = { file => 'my_document.txt',
the_date => $db->newCommand('CUR_DATE()')
};
$db->insert('my_doc_table', $data);This can also be done by passing a reference to a string with the SQL command, e.g.,
my $data = { file => 'my_document.txt',
the_date => \'CUR_DATE()'
};
$db->insert('my_doc_table', $data);command($cmd_string), literal($cmd_string), sql_literal($cmd_string)
This creates a literal SQL command for use in insert(), update(), and related methods, since if you simply put something like "CUR_DATE()" as a value in the %data parameter passed to insert, the function will get quoted, and so will not work as expected. Instead, do something like this:
my $data = { file => 'my_document.txt',
the_date => $db->command('CUR_DATE()')
};
$db->insert('my_doc_table', $data);This can also be done by passing a reference to a string with the SQL command, e.g.,
my $data = { file => 'my_document.txt',
the_date => \'CUR_DATE()'
};
$db->insert('my_doc_table', $data);This is currently how command() is implemented.
debugOn(\*FILE_HANDLE)
Turns on debugging output. Debugging information will be printed to the given filehandle.
debugOff()
Turns off debugging output.
setNameArg($arg)
This is the argument to pass to the fetchrow_hashref() call on the underlying DBI object. By default, this is 'NAME_lc', so that all field names returned are all lowercase to provide for portable code. If you want to make all the field names return be uppercase, call $db->setNameArg('NAME_uc') after the connect() call. And if you really want the case of the field names to be what the underlying database driveer returns them as, call $db->setNameArg('NAME').
err()
Calls err() on the underlying DBI object, which returns the native database engine error code from the last driver method called.
errstr()
Calls errstr() on the underlying DBI object, which returns the native database engine error message from the last driver method called.
DBI methods
The following method calls are just passed through to the
underlying DBI object for convenience. See the documentation
for DBI for details.- prepare
-
This method may call hooks in the future. Use prepare_no_hooks() if you want to ensure that it will be a simple DBI call.
- selectrow_arrayref
- selectrow_hashref
- selectall_arrayref
- selectall_hashref
- selectcol_arrayref
- do
- quote
- commit
- begin_work
- rollback
- ping
getLastInsertId(), get_last_insert_id(), last_insert_id()
Returns the last_insert_id. The default is to be MySQL
specific. It just runs the query "SELECT LAST_INSERT_ID()".
However, it will also work with MSSQL with the right parameters
(see the db_style parameter in the section explaining the
connect() method).Hooks
DBIx::Wrapper supports hooks that get called just before and just after various query operations. The add*Hook methods take a single argument that is either a code reference (e.g., anonymous subroutine reference), or an array whose first element is an object and whose second element is the name of a method to call on that object.
The hooks will be called with a request object as the first argument. See DBIx::Wrapper::Request.
The two expected return values are $request->OK and $request->DECLINED. The first tells DBIx::Wrapper that the current hook has done everything that needs to be done and doesn't call any other hooks in the stack for the current request. DECLINED tells DBIx::Wrapper to continue down the hook stack as if the current handler was never invoked.
See DBIx::Wrapper::Request for example hooks.
addPrePrepareHook($hook)
Specifies a hook to be called just before any SQL statement is prepare()'d.
addPostPrepareHook($hook)
Specifies a hook to be called just after any SQL statement is prepare()'d.
addPreExecHook($hook)
Specifies a hook to be called just before any SQL statement is execute()'d.
addPostExecHook($hook)
Adds a hook to be called just after a statement is execute()'d.
addPreFetchHook($hook)
Adds a hook to be called just before data is fetch()'d from the server.
addPostFetchHook($hook)
Adds a hook to be called just after data is fetch()'d from the server.
There are also underscore_separated versions of these methods.
E.g., nativeSelectLoop() becomes native_select_loop()DEPENDENCIES
DBIACKNOWLEDGEMENTS
Others who have contributed ideas and/or code for this module:
Kevin Wilson
Mark Stosberg
David BushongAUTHOR
Don Owens <don@owensnet.com>LICENSE AND COPYRIGHT
Copyright (c) 2003-2005 Don Owens (don@owensnet.com). All rights reserved.
This free software; you can redistribute it and/or modify it under the same terms as Perl itself. See perlartistic.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
SEE ALSO
DBIVERSION
0.201 POD Error
The following errors were encountered while parsing the POD:
- Around line 2612:
You forgot a '=back' before '=head2'