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Data::Printer::Filter:User3Contributed Perl DocumeData::Printer::Filter::DB(3)

NAME
       Data::Printer::Filter::DB - pretty printing database objects

SYNOPSIS
       In your program:

	 use Data::Printer filters => {
	     -external => [ 'DB' ],
	 };

       or, in your ".dataprinter" file:

	 {
	   filters => {
	     -external => [ 'DB' ],
	   },
	 };

DESCRIPTION
       This is a filter	plugin for Data::Printer. It filters through DBI's
       handlers	(dbh) and statement (sth) objects displaying relevant
       information for the user.  It also filters any object which inherits
       from DBIx::Class::Schema, DBIx::Class::ResultSet	or
       DBIx::Class::ResultSetColumn.

   DBI Sample Output
       DBI is an extremely powerful and	complete database interface. But it
       does a lot of magic under the hood, making their	objects	somewhat
       harder to debug.	This filter aims to fix	that :)

       For instance, say you want to debug something like this:

	 use DBI;
	 my $dbh = DBI->connect('dbi:DBM(RaiseError=1):', undef, undef );

       A regular Data::Dumper output gives you absolutely nothing:

       $VAR1 = bless( {}, 'DBI::db' );

       Data::Printer makes it better, but only to debug	the class itself, not
       helpful at all to see its contents and debug your own code:

	   DBI::db  {
	       Parents	     DBI::common
	       Linear @ISA   DBI::db, DBI::common
	       public methods (48) : begin_work, clone,	column_info, commit, connected,	data_sources, disconnect, do, foreign_key_info,	get_info, last_insert_id, ping,	prepare, prepare_cached, preparse, primary_key,	primary_key_info, quote, quote_identifier, rollback, rows, selectall_arrayref, selectall_hashref, selectcol_arrayref, selectrow_array, selectrow_arrayref, selectrow_hashref, sqlite_backup_from_file, sqlite_backup_to_file, sqlite_busy_timeout, sqlite_collation_needed, sqlite_commit_hook,	sqlite_create_aggregate, sqlite_create_collation, sqlite_create_function, sqlite_enable_load_extension,	sqlite_last_insert_rowid, sqlite_progress_handler, sqlite_register_fts3_perl_tokenizer,	sqlite_rollback_hook, sqlite_set_authorizer, sqlite_update_hook, statistics_info, table_info, tables, take_imp_data, type_info,	type_info_all
	       private methods (0)
	       internals: {
	       }
	   }

       Fear no more! If	you use	this filter, here's what you'll	see:

	   SQLite Database Handle (connected) {
	       dbname: file.db
	       Auto Commit: 1
	       Statement Handles: 0
	       Last Statement: -
	   }

       Much better, huh? :)

       Statement handlers are even better. Imagine you continued your code
       with something like:

	 my $sth = $dbh->prepare('SELECT * FROM	foo WHERE bar =	?');
	 $sth->execute(42);

       With this filter, instead of an empty dump or full method information,
       you'll get exactly what you came	for:

	SELECT * FROM foo WHERE	bar = ?	 (42)

       Note that if your driver	does not support holding of parameter values,
       you'll get a "bindings unavailable" message instead of the bound
       values.

SEE ALSO
       Data::Printer, Data::Printer::Filter

perl v5.24.1			  2017-04-15	  Data::Printer::Filter::DB(3)

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO

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