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

Comparing PApp-SQL/SQL.pm (file contents):
Revision 1.8 by root, Mon Jan 22 10:53:36 2001 UTC vs.
Revision 1.21 by root, Wed Feb 27 04:32:39 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 eb 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
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	$dbh = connect_cached __FILE__, "DBI:mysql:papp";
76		127
		128	Mysql-specific behaviour: The default setting of
		129	C<mysql_client_found_rows> is TRUE, you can overwrite this, though.
		130
77	=cut	131	=cut
78		132
79	sub connect_cached {	133	sub connect_cached {
80	my ($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 $sth = sql_uexec <see sql_exec>
		159
99	C<sql_exec> is the most important and most-used function in this module.	160	C<sql_exec> is the most important and most-used function in this module.
100		161
101	Runs the given sql command with the given parameters and returns the	162	Runs the given sql command with the given parameters and returns the
102	statement handle. The command and the statement handle will be cached	163	statement handle. The command and the statement handle will be cached
103	(with the database handle and the sql string as key), so prepare will be	164	(with the database handle and the sql string as key), so prepare will be
…		…
114	The actual return value from the C<$sth->execute> call is stored in the	175	The actual return value from the C<$sth->execute> call is stored in the
115	package-global (and exported) variable C<$sql_exec>.	176	package-global (and exported) variable C<$sql_exec>.
116		177
117	If any error occurs C<sql_exec> will throw an exception.	178	If any error occurs C<sql_exec> will throw an exception.
118		179
		180	C<sql_uexec> is similar to C<sql_exec> but upgrades all input arguments to
		181	utf8 before calling the C<execute> method.
		182
119	Examples:	183	Examples:
120		184
121	# easy one	185	# easy one
122	my $st = sql_exec "select name, id from table where id = ?", $id;	186	my $st = sql_exec "select name, id from table where id = ?", $id;
123	while (my ($name, $id) = $st->fetchrow_array) { ... };	187	while (my ($name, $id) = $st->fetchrow_array) { ... };
…		…
132	sql_exec $dbh, "update file set name = ?", "oops.txt";	196	sql_exec $dbh, "update file set name = ?", "oops.txt";
133		197
134		198
135	=item sql_fetch <see sql_exec>	199	=item sql_fetch <see sql_exec>
136		200
		201	=item sql_ufetch <see sql_uexec>
		202
137	Execute a sql-statement and fetch the first row of results. Depending on	203	Execute an sql-statement and fetch the first row of results. Depending on
138	the caller context the row will be returned as a list (array context), or	204	the caller context the row will be returned as a list (array context), or
139	just the first columns. In table form:	205	just the first columns. In table form:
140		206
141	CONTEXT RESULT	207	CONTEXT RESULT
142	void ()	208	void ()
…		…
153		219
154	my($name, $amount) = sql_fetch "select ...", args...	220	my($name, $amount) = sql_fetch "select ...", args...
155		221
156	... and it's still quite fast unless you fetch large amounts of data.	222	... and it's still quite fast unless you fetch large amounts of data.
157		223
		224	C<sql_ufetch> is similar to C<sql_fetch> but upgrades all input values to
		225	utf8 and forces all result values to utf8 (this does I<not> include result
		226	parameters, only return values. Using bind variables in cinjunction with
		227	sql_u* functions results in undefined behaviour).
		228
158	=item sql_fetchall <see sql_exec>	229	=item sql_fetchall <see sql_exec>
		230
		231	=item sql_ufetchall <see sql_uexec>
159		232
160	Similarly to C<sql_fetch>, but all result rows will be fetched (this is	233	Similarly to C<sql_fetch>, but all result rows will be fetched (this is
161	of course inefficient for large results!). The context is ignored (only	234	of course inefficient for large results!). The context is ignored (only
162	list context makes sense), but the result still depends on the number of	235	list context makes sense), but the result still depends on the number of
163	columns in the result:	236	columns in the result:
…		…
175		248
176	for (sql_fetchall "select name, age, place from user") {	249	for (sql_fetchall "select name, age, place from user") {
177	my ($name, $age, $place) = @$_;	250	my ($name, $age, $place) = @$_;
178	}	251	}
179		252
		253	C<sql_ufetchall> is similar to C<sql_fetchall> but upgrades all input
		254	values to utf8 and forces all result values to utf8 (see the caveats in
		255	the description of C<sql_ufetch>, though).
		256
180	=item sql_exists "<table> where ...", args...	257	=item sql_exists "<table_references> where <where_condition>...", args...
		258
		259	=item sql_uexists <see sql_exists>
181		260
182	Check wether the result of the sql-statement "select xxx from	261	Check wether the result of the sql-statement "select xxx from
183	$first_argument" would be empty or not (that is, imagine the string	262	$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	263	"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	264	with every database but can be quite slow, except on mysql, where this
186	should be quite fast.	265	should be quite fast.
		266
		267	C<sql_uexists> is similar to C<sql_exists> but upgrades all parameters to
		268	utf8.
187		269
188	Examples:	270	Examples:
189		271
190	print "user 7 exists!\n"	272	print "user 7 exists!\n"
191	if sql_exists "user where id = ?", 7;	273	if sql_exists "user where id = ?", 7;
…		…
241		323
242	=cut	324	=cut
243		325
244	=item reinitialize [not exported]	326	=item reinitialize [not exported]
245		327
246	Clears any internal caches (statement cache, database handle cache).	328	Clears any internal caches (statement cache, database handle
		329	cache). Should be called after C<fork> and other accidents that invalidate
		330	database handles.
247		331
248	=cut	332	=cut
249		333
250	sub reinitialize {	334	sub reinitialize {
251	cachesize cachesize 0;	335	cachesize cachesize 0;
252	for (values %dbcache) {	336	for (values %dbcache) {
253	eval { $_->disconnect };	337	eval { $_->{InactiveDestroy} = 1 };
254	}	338	}
255	undef %dbcache;	339	undef %dbcache;
256	}	340	}
257		341
258	=back	342	=back
…		…
263		347
264	package PApp::SQL::Database;	348	package PApp::SQL::Database;
265		349
266	=head2 THE DATABASE CLASS	350	=head2 THE DATABASE CLASS
267		351
268	Again (sigh) the problem of persistency. What do you do when you have to serialize on object	352	Again (sigh) the problem of persistency. What do you do when you have
269	that contains (or should contain) a database handle? Short answer: you don't. Long answer:	353	to serialize on object that contains (or should contain) a database
		354	handle? Short answer: you don't. Long answer: you can embed the necessary
270	you can embed the necessary information to recreate the dbh when needed.	355	information to recreate the dbh when needed.
271		356
272	The C<PApp::SQL::Database> class does that, in a relatively efficient	357	The C<PApp::SQL::Database> class does that, in a relatively efficient
273	fashion: the overhead is currently a single method call per access (you	358	fashion: the overhead is currently a single method call per access (you
274	can cache the real dbh if you want).	359	can cache the real dbh if you want).
275		360
…		…
315		400
316	=item $db->dsn	401	=item $db->dsn
317		402
318	Return the DSN (L<DBI>) fo the database object (e.g. for error messages).	403	Return the DSN (L<DBI>) fo the database object (e.g. for error messages).
319		404
		405	=item $db->login
		406
		407	Return the login name.
		408
		409	=item $db->password
		410
		411	Return the password (emphasizing the fact that the apssword is stored plaintext ;)
		412
320	=cut	413	=cut
321		414
322	sub dsn($) {	415	sub dsn($) {
323	my $self = shift;	416	my $self = shift;
324	$self->[1][1];	417	(split /\x00/, $self->[0])[1];
		418	}
		419
		420	sub login($) {
		421	my $self = shift;
		422	(split /\x00/, $self->[0])[2];
		423	}
		424
		425	sub password($) {
		426	my $self = shift;
		427	(split /\x00/, $self->[0])[3];
325	}	428	}
326		429
327	=back	430	=back
328		431
329	=cut	432	=cut
330		433
331	1;	434	1;
332
333	=head1 BUGS
334
335	As of this writing, sql_fetch and sql_fetchall are not very well tested
336	(they were just re-written in C).
337
338	sql_exists could be faster (it is written very ugly to not change the
339	current package).
340		435
341	=head1 SEE ALSO	436	=head1 SEE ALSO
342		437
343	L<PApp>.	438	L<PApp>.
344		439

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Comparing PApp-SQL/SQL.pm (file contents): Revision 1.8 by root, Mon Jan 22 10:53:36 2001 UTC vs. Revision 1.21 by root, Wed Feb 27 04:32:39 2002 UTC

Diff Legend

Comparing PApp-SQL/SQL.pm (file contents):
Revision 1.8 by root, Mon Jan 22 10:53:36 2001 UTC vs.
Revision 1.21 by root, Wed Feb 27 04:32:39 2002 UTC