[ViewVC] Diff of: cvs/PApp-SQL/SQL.pm

Comparing PApp-SQL/SQL.pm (file contents):
Revision 1.9 by root, Sat Feb 3 17:48:02 2001 UTC vs.
Revision 1.23 by root, Sun Apr 7 16:23:56 2002 UTC

…		…
1	=head1 NAME	1	=head1 NAME
2		2
3	PApp::SQL - absolutely easy yet fast and powerful sql access	3	PApp::SQL - absolutely easy yet fast and powerful sql access.
4		4
5	=head1 SYNOPSIS	5	=head1 SYNOPSIS
6		6
7	use PApp::SQL;	7	use PApp::SQL;
8	# to be written	8
		9	my $st = sql_exec $DBH, "select ... where a = ?", $a;
		10
		11	local $DBH = <database handle>;
		12	my $st = sql_exec \my($bind_a, $bind_b), "select a,b ...";
		13	my $st = sql_insertid
		14	sql_exec "insert into ... values (?, ?)", $v1, $v2;
		15	my $a = sql_fetch "select a from ...";
		16	sql_fetch \my($a, $b), "select a,b ...";
		17
		18	sql_exists "table where name like 'a%'"
		19	or die "a* required but not existent";
		20
		21	my $db = new PApp::SQL::Database "", "DBI:mysql:test", "user", "pass";
		22	local $PApp::SQL::DBH = $db->checked_dbh; # does 'ping'
		23
		24	sql_exec $db->dbh, "select ...";
9		25
10	=head1 DESCRIPTION	26	=head1 DESCRIPTION
11		27
12	This module provides you with easy-to-use functions to execute sql	28	This module provides you with easy-to-use functions to execute sql
13	commands (using DBI). Despite being easy to use, they are also quite	29	commands (using DBI). Despite being easy to use, they are also quite
14	efficient and allow you to write faster programs in less lines of code.	30	efficient and allow you to write faster programs in less lines of code. It
		31	should work with anything from perl-5.004_01 onwards, but I only support
		32	5.005+. UTF8 handling (the C<sql_u*> family of functions) will only be
		33	effective with perl version 5.006 and beyond.
15		34
16	=over 4	35	If the descriptions here seem terse or if you always wanted to know
		36	what PApp is then have a look at the PApp module which uses this module
		37	extensively but also provides you with a lot more gimmicks to play around
		38	with to help you create cool applications ;)
17		39
18	=cut	40	=cut
19		41
20	package PApp::SQL;	42	package PApp::SQL;
21		43
22	use DBI;	44	use DBI ();
23
24	#use PApp::Exception; # not yet used
25		45
26	BEGIN {	46	BEGIN {
27	use base Exporter;	47	use base qw(Exporter DynaLoader);
28		48
29	$VERSION = 0.11;	49	$VERSION = 0.13;
30	@EXPORT = qw(	50	@EXPORT = qw(
31	sql_exec sql_fetch sql_fetchall sql_exists sql_insertid $sql_exec	51	sql_exec sql_fetch sql_fetchall sql_exists sql_insertid $sql_exec
		52	sql_uexec sql_ufetch sql_ufetchall sql_uexists
32	);	53	);
33	@EXPORT_OK = qw(	54	@EXPORT_OK = qw(
34	connect_cached	55	connect_cached
35	);	56	);
36		57
37	require XSLoader;	58	bootstrap PApp::SQL $VERSION;
38	XSLoader::load PApp::SQL, $VERSION;
39	}	59	}
40		60
41	our $sql_exec; # last result of sql_exec's execute call	61	our $sql_exec; # last result of sql_exec's execute call
42	our $DBH; # the default database handle	62	our $DBH; # the default database handle
43	our $database; # the current SQL::Database object, if applicable	63	our $Database; # the current SQL::Database object, if applicable
44		64
45	our %dbcache;	65	our %dbcache;
		66
		67	=head2 GLOBAL VARIABLES
		68
		69	=over 4
		70
		71	=item $sql_exec
		72
		73	Since the C<sql_exec> family of functions return a statement handle there
		74	must be another way to test the return value of the C<execute> call. This
		75	global variable contains the result of the most recent call to C<execute>
		76	done by this module.
		77
		78	=item $PApp::SQL::DBH
		79
		80	The default database handle used by this module if no C<$DBH> was
		81	specified as argument and no C<$DBH> is found in the current package. See
		82	C<sql_exec> for a discussion.
		83
		84	=item $PApp::SQL::Database
		85
		86	The current default C<PApp::SQL::Database>-object. Future versions might
		87	automatically fall back on this database and create database handles from
		88	it if neccessary. At the moment this is not used by this module but might
		89	be nice as a placeholder for the database object that corresponds to
		90	$PApp::SQL::DBH.
		91
		92	=back
		93
		94	=head2 FUNCTIONS
		95
		96	=over 4
46		97
47	=item $dbh = connect_cached $id, $dsn, $user, $pass, $flags, $connect	98	=item $dbh = connect_cached $id, $dsn, $user, $pass, $flags, $connect
48		99
49	(not exported by by default)	100	(not exported by by default)
50		101
60	__LINE__ work fine as well).	111	__LINE__ work fine as well).
61		112
62	The reason C<$id> is necessary is that you might specify special connect	113	The reason C<$id> is necessary is that you might specify special connect
63	arguments or special flags, or you might want to configure your $DBH	114	arguments or special flags, or you might want to configure your $DBH
64	differently than maybe other applications requesting the same database	115	differently than maybe other applications requesting the same database
65	connection. If none of this is becessary for your application you can	116	connection. If none of this is necessary for your application you can
66	leave $id empty (i.e. "").	117	leave C<$id> empty (i.e. "").
67		118
68	If specified, C<$connect> is a callback (e.g. a coderef) that will be	119	If specified, C<$connect> is a callback (e.g. a coderef) that will be
69	called each time a new connection is being established, with the new	120	called each time a new connection is being established, with the new
70	C<$dbh> as first argument.	121	C<$dbh> as first argument.
71		122
72	Examples:	123	Examples:
73		124
74	# try your luck opening the papp database without access info	125	# try your luck opening the papp database without access info
75	$dbh = connect_cached __FILE__, "DBI:mysql:papp";	126	$dbh = connect_cached __FILE__, "DBI:mysql:papp";
		127
		128	Mysql-specific behaviour: The default setting of
		129	C<mysql_client_found_rows> is TRUE, you can overwrite this, though.
76		130
77	=cut	131	=cut
78		132
79	sub connect_cached {	133	sub connect_cached {
80	my ($id, $dsn, $user, $pass, $flags, $connect) = @_;	134	my ($id, $dsn, $user, $pass, $flags, $connect) = @_;
81	# the following line is duplicated in PApp::SQL::Database::new	135	# the following line is duplicated in PApp::SQL::Database::new
82	$id = "$id\0$dsn\0$user\0$pass";	136	$id = "$id\0$dsn\0$user\0$pass";
83	unless ($dbcache{$id} && $dbcache{$id}->ping) {	137	unless ($dbcache{$id} && $dbcache{$id}->ping) {
84	#warn "connecting to ($dsn\|$user\|$pass\|$flags)\n";#d#
85	# first, nuke our statement cache (sooory ;)	138	# first, nuke our statement cache (sooory ;)
86	cachesize cachesize 0;	139	cachesize cachesize 0;
		140
		141	# then make mysql behave more standardly by default
		142	$dsn =~ /^[Dd][Bb][Ii]:mysql:/
		143	and $dsn !~ /;mysql_client_found_rows/
		144	and $dsn .= ";mysql_client_found_rows=1";
		145
87	# then connect anew	146	# then connect anew
88	$dbcache{$id} =	147	$dbcache{$id} =
89	eval { DBI->connect($dsn, $user, $pass, $flags) }	148	eval { DBI->connect($dsn, $user, $pass, $flags) }
90	\|\| eval { DBI->connect($dsn, $user, $pass, $flags) }	149	\|\| eval { DBI->connect($dsn, $user, $pass, $flags) }
91	\|\| die "unable to connect to database $dsn: $DBI::errstr\n";	150	\|\| die "unable to connect to database $dsn: $DBI::errstr\n";
…		…
94	$dbcache{$id};	153	$dbcache{$id};
95	}	154	}
96		155
97	=item $sth = sql_exec [dbh,] [bind-vals...,] "sql-statement", [arguments...]	156	=item $sth = sql_exec [dbh,] [bind-vals...,] "sql-statement", [arguments...]
98		157
		158	=item $sth = sql_uexec <see sql_exec>
		159
99	C<sql_exec> is the most important and most-used function in this module.	160	C<sql_exec> is the most important and most-used function in this module.
100		161
101	Runs the given sql command with the given parameters and returns the	162	Runs the given sql command with the given parameters and returns the
102	statement handle. The command and the statement handle will be cached	163	statement handle. The command and the statement handle will be cached
103	(with the database handle and the sql string as key), so prepare will be	164	(with the database handle and the sql string as key), so prepare will be
104	called only once for each distinct sql call (please keep in mind that the	165	called only once for each distinct sql call (please keep in mind that the
105	returned statement will always be the same, so, if you call C<sql_exec>	166	returned statement will always be the same, so, if you call C<sql_exec>
106	with the same dbh and sql-statement twice (e.g. in a subroutine you	167	with the same dbh and sql-statement twice (e.g. in a subroutine you
107	called), the statement handle for the first call mustn't be used.	168	called), the statement handle for the first call mustn't not be in use
		169	anymore, as the subsequent call will re-use the handle.
108		170
109	The database handle (the first argument) is optional. If it is missing,	171	The database handle (the first argument) is optional. If it is missing,
110	C<sql_exec> first tries to use the variable C<$DBH> in the current (=	172	C<sql_exec> first tries to use the variable C<$DBH> in the current (=
111	calling) package and, if that fails, it tries to use database handle in	173	calling) package and, if that fails, it tries to use database handle in
112	C<$PApp::SQL::DBH>, which you can set before calling these functions.	174	C<$PApp::SQL::DBH>, which you can set before calling these functions.
113		175
114	The actual return value from the C<$sth->execute> call is stored in the	176	The actual return value from the C<$sth->execute> call is stored in the
115	package-global (and exported) variable C<$sql_exec>.	177	package-global (and exported) variable C<$sql_exec>.
116		178
117	If any error occurs C<sql_exec> will throw an exception.	179	If any error occurs C<sql_exec> will throw an exception.
		180
		181	C<sql_uexec> is similar to C<sql_exec> but upgrades all input arguments to
		182	utf8 before calling the C<execute> method.
118		183
119	Examples:	184	Examples:
120		185
121	# easy one	186	# easy one
122	my $st = sql_exec "select name, id from table where id = ?", $id;	187	my $st = sql_exec "select name, id from table where id = ?", $id;
…		…
132	sql_exec $dbh, "update file set name = ?", "oops.txt";	197	sql_exec $dbh, "update file set name = ?", "oops.txt";
133		198
134		199
135	=item sql_fetch <see sql_exec>	200	=item sql_fetch <see sql_exec>
136		201
		202	=item sql_ufetch <see sql_uexec>
		203
137	Execute a sql-statement and fetch the first row of results. Depending on	204	Execute an sql-statement and fetch the first row of results. Depending on
138	the caller context the row will be returned as a list (array context), or	205	the caller context the row will be returned as a list (array context), or
139	just the first columns. In table form:	206	just the first columns. In table form:
140		207
141	CONTEXT RESULT	208	CONTEXT RESULT
142	void ()	209	void ()
…		…
153		220
154	my($name, $amount) = sql_fetch "select ...", args...	221	my($name, $amount) = sql_fetch "select ...", args...
155		222
156	... and it's still quite fast unless you fetch large amounts of data.	223	... and it's still quite fast unless you fetch large amounts of data.
157		224
		225	C<sql_ufetch> is similar to C<sql_fetch> but upgrades all input values to
		226	utf8 and forces all result values to utf8 (this does I<not> include result
		227	parameters, only return values. Using bind variables in cinjunction with
		228	sql_u* functions results in undefined behaviour).
		229
158	=item sql_fetchall <see sql_exec>	230	=item sql_fetchall <see sql_exec>
		231
		232	=item sql_ufetchall <see sql_uexec>
159		233
160	Similarly to C<sql_fetch>, but all result rows will be fetched (this is	234	Similarly to C<sql_fetch>, but all result rows will be fetched (this is
161	of course inefficient for large results!). The context is ignored (only	235	of course inefficient for large results!). The context is ignored (only
162	list context makes sense), but the result still depends on the number of	236	list context makes sense), but the result still depends on the number of
163	columns in the result:	237	columns in the result:
…		…
175		249
176	for (sql_fetchall "select name, age, place from user") {	250	for (sql_fetchall "select name, age, place from user") {
177	my ($name, $age, $place) = @$_;	251	my ($name, $age, $place) = @$_;
178	}	252	}
179		253
		254	C<sql_ufetchall> is similar to C<sql_fetchall> but upgrades all input
		255	values to utf8 and forces all result values to utf8 (see the caveats in
		256	the description of C<sql_ufetch>, though).
		257
180	=item sql_exists "<table> where ...", args...	258	=item sql_exists "<table_references> where <where_condition>...", args...
		259
		260	=item sql_uexists <see sql_exists>
181		261
182	Check wether the result of the sql-statement "select xxx from	262	Check wether the result of the sql-statement "select xxx from
183	$first_argument" would be empty or not (that is, imagine the string	263	$first_argument" would be empty or not (that is, imagine the string
184	"select from" were prepended to your statement (it isn't)). Should work	264	"select * from" were prepended to your statement (it isn't)). Should work
185	with every database but can be quite slow, except on mysql, where this	265	with every database but can be quite slow, except on mysql, where this
186	should be quite fast.	266	should be quite fast.
		267
		268	C<sql_uexists> is similar to C<sql_exists> but upgrades all parameters to
		269	utf8.
187		270
188	Examples:	271	Examples:
189		272
190	print "user 7 exists!\n"	273	print "user 7 exists!\n"
191	if sql_exists "user where id = ?", 7;	274	if sql_exists "user where id = ?", 7;
…		…
250	=cut	333	=cut
251		334
252	sub reinitialize {	335	sub reinitialize {
253	cachesize cachesize 0;	336	cachesize cachesize 0;
254	for (values %dbcache) {	337	for (values %dbcache) {
255	eval { $_->disconnect };	338	eval { $_->{InactiveDestroy} = 1 };
256	}	339	}
257	undef %dbcache;	340	undef %dbcache;
258	}	341	}
259		342
260	=back	343	=back
…		…
265		348
266	package PApp::SQL::Database;	349	package PApp::SQL::Database;
267		350
268	=head2 THE DATABASE CLASS	351	=head2 THE DATABASE CLASS
269		352
270	Again (sigh) the problem of persistency. What do you do when you have to serialize on object	353	Again (sigh) the problem of persistency. What do you do when you have
271	that contains (or should contain) a database handle? Short answer: you don't. Long answer:	354	to serialize on object that contains (or should contain) a database
		355	handle? Short answer: you don't. Long answer: you can embed the necessary
272	you can embed the necessary information to recreate the dbh when needed.	356	information to recreate the dbh when needed.
273		357
274	The C<PApp::SQL::Database> class does that, in a relatively efficient	358	The C<PApp::SQL::Database> class does that, in a relatively efficient
275	fashion: the overhead is currently a single method call per access (you	359	fashion: the overhead is currently a single method call per access (you
276	can cache the real dbh if you want).	360	can cache the real dbh if you want).
277		361
…		…
317		401
318	=item $db->dsn	402	=item $db->dsn
319		403
320	Return the DSN (L<DBI>) fo the database object (e.g. for error messages).	404	Return the DSN (L<DBI>) fo the database object (e.g. for error messages).
321		405
		406	=item $db->login
		407
		408	Return the login name.
		409
		410	=item $db->password
		411
		412	Return the password (emphasizing the fact that the apssword is stored plaintext ;)
		413
322	=cut	414	=cut
323		415
324	sub dsn($) {	416	sub dsn($) {
325	my $self = shift;	417	my $self = shift;
326	(split /\x00/, $self->[0])[1];	418	(split /\x00/, $self->[0])[1];
327	}	419	}
328		420
		421	sub login($) {
		422	my $self = shift;
		423	(split /\x00/, $self->[0])[2];
		424	}
		425
		426	sub password($) {
		427	my $self = shift;
		428	(split /\x00/, $self->[0])[3];
		429	}
		430
329	=back	431	=back
330		432
331	=cut	433	=cut
332		434
333	1;	435	1;
334
335	=head1 BUGS
336
337	As of this writing, sql_fetch and sql_fetchall are not very well tested
338	(they were just re-written in C).
339
340	sql_exists could be faster (it is written very ugly to not change the
341	current package).
342		436
343	=head1 SEE ALSO	437	=head1 SEE ALSO
344		438
345	L<PApp>.	439	L<PApp>.
346		440

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Comparing PApp-SQL/SQL.pm (file contents): Revision 1.9 by root, Sat Feb 3 17:48:02 2001 UTC vs. Revision 1.23 by root, Sun Apr 7 16:23:56 2002 UTC

Diff Legend

Comparing PApp-SQL/SQL.pm (file contents):
Revision 1.9 by root, Sat Feb 3 17:48:02 2001 UTC vs.
Revision 1.23 by root, Sun Apr 7 16:23:56 2002 UTC