… | |
… | |
8 | |
8 | |
9 | my $st = sql_exec $DBH, "select ... where a = ?", $a; |
9 | my $st = sql_exec $DBH, "select ... where a = ?", $a; |
10 | |
10 | |
11 | local $DBH = <database handle>; |
11 | local $DBH = <database handle>; |
12 | my $st = sql_exec \my($bind_a, $bind_b), "select a,b ..."; |
12 | my $st = sql_exec \my($bind_a, $bind_b), "select a,b ..."; |
13 | my $st = sql_insertid |
13 | my $id = sql_insertid |
14 | sql_exec "insert into ... values (?, ?)", $v1, $v2; |
14 | sql_exec "insert into ... values (?, ?)", $v1, $v2; |
15 | my $a = sql_fetch "select a from ..."; |
15 | my $a = sql_fetch "select a from ..."; |
16 | sql_fetch \my($a, $b), "select a,b ..."; |
16 | sql_fetch \my($a, $b), "select a,b ..."; |
17 | |
17 | |
18 | sql_exists "name from table where name like 'a%'" |
18 | sql_exists "table where name like 'a%'" |
19 | or die "a* required but not existent"; |
19 | or die "a* required but not existent"; |
20 | |
20 | |
21 | my $db = new PApp::SQL::Database "", "DBI:mysql:test", "user", "pass"; |
21 | my $db = new PApp::SQL::Database "", "DBI:mysql:test", "user", "pass"; |
22 | local $PApp::SQL::DBH = $db->checked_dbh; # does 'ping' |
22 | local $PApp::SQL::DBH = $db->checked_dbh; # does 'ping' |
23 | |
23 | |
… | |
… | |
25 | |
25 | |
26 | =head1 DESCRIPTION |
26 | =head1 DESCRIPTION |
27 | |
27 | |
28 | 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 |
29 | 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 |
30 | efficient and allow you to write faster programs in less lines of code. It |
30 | efficient and allow you to write faster programs in fewer lines of |
31 | should work with anything from perl-5.004_01 onwards, but I only support |
31 | code. It should work with anything from perl-5.004_01 onwards, but I only |
32 | 5.005+. UTF8 handling (the C<sql_u*> family of functions) will only be |
32 | support 5.005+. UTF8 handling (the C<sql_u*> family of functions) will |
33 | effective with perl version 5.006 and beyond. |
33 | only be effective with perl version 5.006 and beyond. |
34 | |
34 | |
35 | If the descriptions here seem terse or if you always wanted to know |
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 |
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 |
37 | extensively but also provides you with a lot more gimmicks to play around |
38 | with to help you create cool applications ;) |
38 | with to help you create cool applications ;) |
39 | |
39 | |
40 | =cut |
40 | =cut |
41 | |
41 | |
42 | package PApp::SQL; |
42 | package PApp::SQL; |
43 | |
43 | |
|
|
44 | use Carp (); |
44 | use DBI (); |
45 | use DBI (); |
45 | |
46 | |
46 | BEGIN { |
47 | BEGIN { |
47 | use base qw(Exporter DynaLoader); |
48 | use base qw(Exporter DynaLoader); |
48 | |
49 | |
49 | $VERSION = 0.1241; |
50 | $VERSION = '2.002'; |
50 | @EXPORT = qw( |
51 | @EXPORT = qw( |
51 | sql_exec sql_fetch sql_fetchall sql_exists sql_insertid $sql_exec |
52 | sql_exec sql_fetch sql_fetchall sql_exists sql_insertid $sql_exec |
52 | sql_uexec sql_ufetch sql_ufetchall sql_uexists |
53 | sql_uexec sql_ufetch sql_ufetchall sql_uexists |
53 | ); |
54 | ); |
54 | @EXPORT_OK = qw( |
55 | @EXPORT_OK = qw( |
… | |
… | |
56 | ); |
57 | ); |
57 | |
58 | |
58 | bootstrap PApp::SQL $VERSION; |
59 | bootstrap PApp::SQL $VERSION; |
59 | } |
60 | } |
60 | |
61 | |
|
|
62 | boot2 DBI::SQL_VARCHAR, DBI::SQL_INTEGER, DBI::SQL_DOUBLE; |
|
|
63 | |
61 | our $sql_exec; # last result of sql_exec's execute call |
64 | our $sql_exec; # last result of sql_exec's execute call |
62 | our $DBH; # the default database handle |
65 | our $DBH; # the default database handle |
63 | our $Database; # the current SQL::Database object, if applicable |
66 | our $Database; # the current SQL::Database object, if applicable |
64 | |
67 | |
65 | our %dbcache; |
68 | our %dbcache; |
66 | |
69 | |
67 | =head2 GLOBAL VARIABLES |
70 | =head2 Global Variables |
68 | |
71 | |
69 | =over 4 |
72 | =over 4 |
70 | |
73 | |
71 | =item $sql_exec |
74 | =item $sql_exec |
72 | |
75 | |
73 | Since the C<sql_exec> family of functions return a statement handle there |
76 | 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 |
77 | 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> |
78 | global variable contains the result of the most recent call to C<execute> |
76 | done by this module. |
79 | done by this module. |
77 | |
80 | |
78 | =item $PApp::SQL::DBH |
81 | =item $PApp::SQL::DBH |
79 | |
82 | |
80 | The default database handle used by this module if no C<$DBH> was |
83 | 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 |
84 | specified as argument. See C<sql_exec> for a discussion. |
82 | C<sql_exec> for a discussion. |
|
|
83 | |
85 | |
84 | =item $PApp::SQL::Database |
86 | =item $PApp::SQL::Database |
85 | |
87 | |
86 | The current default C<PApp::SQL::Database>-object. Future versions might |
88 | The current default C<PApp::SQL::Database>-object. Future versions might |
87 | automatically fall back on this database and create database handles from |
89 | automatically fall back on this database and create database handles from |
… | |
… | |
89 | be nice as a placeholder for the database object that corresponds to |
91 | be nice as a placeholder for the database object that corresponds to |
90 | $PApp::SQL::DBH. |
92 | $PApp::SQL::DBH. |
91 | |
93 | |
92 | =back |
94 | =back |
93 | |
95 | |
94 | =head2 FUNCTIONS |
96 | =head2 Functions |
95 | |
97 | |
96 | =over 4 |
98 | =over 4 |
97 | |
99 | |
98 | =item $dbh = connect_cached $id, $dsn, $user, $pass, $flags, $connect |
100 | =item $dbh = connect_cached $id, $dsn, $user, $pass, $flags, $connect |
99 | |
101 | |
100 | (not exported by by default) |
102 | (not exported by by default) |
101 | |
103 | |
102 | Connect to the database given by C<($dsn,$user,$pass)>, while using the |
104 | Connect to the database given by C<($dsn,$user,$pass)>, while using the |
103 | flags from C<$flags>. These are just the same arguments as given to |
105 | flags from C<$flags>. These are just the same arguments as given to |
104 | C<DBI->connect>. |
106 | C<< DBI->connect >>. |
105 | |
107 | |
106 | The database handle will be cached under the unique id |
108 | The database handle will be cached under the unique id |
107 | C<$id|$dsn|$user|$pass>. If the same id is requested later, the |
109 | C<$id|$dsn|$user|$pass>. If the same id is requested later, the |
108 | cached handle will be checked (using ping), and the connection will |
110 | cached handle will be checked (using ping), and the connection will |
109 | be re-established if necessary (be sure to prefix your application or |
111 | be re-established if necessary (be sure to prefix your application or |
… | |
… | |
111 | __LINE__ work fine as well). |
113 | __LINE__ work fine as well). |
112 | |
114 | |
113 | The reason C<$id> is necessary is that you might specify special connect |
115 | The reason C<$id> is necessary is that you might specify special connect |
114 | arguments or special flags, or you might want to configure your $DBH |
116 | arguments or special flags, or you might want to configure your $DBH |
115 | differently than maybe other applications requesting the same database |
117 | differently than maybe other applications requesting the same database |
116 | connection. If none of this is becessary for your application you can |
118 | connection. If none of this is necessary for your application you can |
117 | leave $id empty (i.e. ""). |
119 | leave C<$id> empty (i.e. ""). |
118 | |
120 | |
119 | If specified, C<$connect> is a callback (e.g. a coderef) that will be |
121 | If specified, C<$connect> is a callback (e.g. a coderef) that will be |
120 | called each time a new connection is being established, with the new |
122 | called each time a new connection is being established, with the new |
121 | C<$dbh> as first argument. |
123 | C<$dbh> as first argument. |
122 | |
124 | |
… | |
… | |
145 | |
147 | |
146 | # then connect anew |
148 | # then connect anew |
147 | $dbcache{$id} = |
149 | $dbcache{$id} = |
148 | eval { DBI->connect($dsn, $user, $pass, $flags) } |
150 | eval { DBI->connect($dsn, $user, $pass, $flags) } |
149 | || eval { DBI->connect($dsn, $user, $pass, $flags) } |
151 | || eval { DBI->connect($dsn, $user, $pass, $flags) } |
150 | || die "unable to connect to database $dsn: $DBI::errstr\n"; |
152 | || Carp::croak "unable to connect to database $dsn: $DBI::errstr\n"; |
151 | $connect->($dbcache{$id}) if $connect; |
153 | $connect->($dbcache{$id}) if $connect; |
152 | } |
154 | } |
153 | $dbcache{$id}; |
155 | $dbcache{$id}; |
154 | } |
156 | } |
155 | |
157 | |
… | |
… | |
163 | statement handle. The command and the statement handle will be cached |
165 | statement handle. The command and the statement handle will be cached |
164 | (with the database handle and the sql string as key), so prepare will be |
166 | (with the database handle and the sql string as key), so prepare will be |
165 | called only once for each distinct sql call (please keep in mind that the |
167 | called only once for each distinct sql call (please keep in mind that the |
166 | returned statement will always be the same, so, if you call C<sql_exec> |
168 | returned statement will always be the same, so, if you call C<sql_exec> |
167 | with the same dbh and sql-statement twice (e.g. in a subroutine you |
169 | with the same dbh and sql-statement twice (e.g. in a subroutine you |
168 | called), the statement handle for the first call mustn't be used. |
170 | called), the statement handle for the first call mustn't not be in use |
|
|
171 | anymore, as the subsequent call will re-use the handle. |
169 | |
172 | |
170 | The database handle (the first argument) is optional. If it is missing, |
173 | The database handle (the first argument) is optional. If it is missing, |
171 | C<sql_exec> first tries to use the variable C<$DBH> in the current (= |
174 | it tries to use database handle in C<$PApp::SQL::DBH>, which you can set |
172 | calling) package and, if that fails, it tries to use database handle in |
175 | before calling these functions. NOTICE: future and former versions of |
173 | C<$PApp::SQL::DBH>, which you can set before calling these functions. |
176 | PApp::SQL might also look up the global variable C<$DBH> in the callers |
|
|
177 | package. |
174 | |
178 | |
|
|
179 | =begin comment |
|
|
180 | |
|
|
181 | If it is missing, C<sql_exec> first tries to use the variable C<$DBH> |
|
|
182 | in the current (= calling) package and, if that fails, it tries to use |
|
|
183 | database handle in C<$PApp::SQL::DBH>, which you can set before calling |
|
|
184 | these functions. |
|
|
185 | |
|
|
186 | =end comment |
|
|
187 | |
175 | The actual return value from the C<$sth->execute> call is stored in the |
188 | The actual return value from the C<< $sth->execute >> call is stored in |
176 | package-global (and exported) variable C<$sql_exec>. |
189 | the package-global (and exported) variable C<$sql_exec>. |
177 | |
190 | |
178 | If any error occurs C<sql_exec> will throw an exception. |
191 | If any error occurs C<sql_exec> will throw an exception. |
179 | |
192 | |
180 | C<sql_uexec> is similar to C<sql_exec> but upgrades all input arguments to |
193 | C<sql_uexec> is similar to C<sql_exec> but upgrades all input arguments to |
181 | utf8 before calling the C<execute> method. |
194 | UTF-8 before calling the C<execute> method. |
182 | |
195 | |
183 | Examples: |
196 | Examples: |
184 | |
197 | |
185 | # easy one |
198 | # easy one |
186 | my $st = sql_exec "select name, id from table where id = ?", $id; |
199 | my $st = sql_exec "select name, id from table where id = ?", $id; |
… | |
… | |
220 | my($name, $amount) = sql_fetch "select ...", args... |
233 | my($name, $amount) = sql_fetch "select ...", args... |
221 | |
234 | |
222 | ... and it's still quite fast unless you fetch large amounts of data. |
235 | ... and it's still quite fast unless you fetch large amounts of data. |
223 | |
236 | |
224 | C<sql_ufetch> is similar to C<sql_fetch> but upgrades all input values to |
237 | C<sql_ufetch> is similar to C<sql_fetch> but upgrades all input values to |
225 | utf8 and forces all result values to utf8. |
238 | UTF-8 and forces all result values to UTF-8 (this does I<not> include result |
|
|
239 | parameters, only return values. Using bind variables in conjunction with |
|
|
240 | sql_u* functions might result in undefined behaviour - we use UTF-8 on |
|
|
241 | bind-variables at execution time and it seems to work on DBD::mysql as it |
|
|
242 | ignores the UTF-8 bit completely. Which just means that that DBD-driver is |
|
|
243 | broken). |
226 | |
244 | |
227 | =item sql_fetchall <see sql_exec> |
245 | =item sql_fetchall <see sql_exec> |
228 | |
246 | |
229 | =item sql_ufetchall <see sql_uexec> |
247 | =item sql_ufetchall <see sql_uexec> |
230 | |
248 | |
… | |
… | |
247 | for (sql_fetchall "select name, age, place from user") { |
265 | for (sql_fetchall "select name, age, place from user") { |
248 | my ($name, $age, $place) = @$_; |
266 | my ($name, $age, $place) = @$_; |
249 | } |
267 | } |
250 | |
268 | |
251 | C<sql_ufetchall> is similar to C<sql_fetchall> but upgrades all input |
269 | C<sql_ufetchall> is similar to C<sql_fetchall> but upgrades all input |
252 | values to utf8 and forces all result values to utf8. |
270 | values to UTF-8 and forces all result values to UTF-8 (see the caveats in |
|
|
271 | the description of C<sql_ufetch>, though). |
253 | |
272 | |
254 | =item sql_exists "<table> where ...", args... |
273 | =item sql_exists "<table_references> where <where_condition>...", args... |
255 | |
274 | |
256 | =item sql_uexists <see sql_exists> |
275 | =item sql_uexists <see sql_exists> |
257 | |
276 | |
258 | Check wether the result of the sql-statement "select xxx from |
277 | Check wether the result of the sql-statement "select xxx from |
259 | $first_argument" would be empty or not (that is, imagine the string |
278 | $first_argument" would be empty or not (that is, imagine the string |
260 | "select * from" were prepended to your statement (it isn't)). Should work |
279 | "select * from" were prepended to your statement (it isn't)). Should work |
261 | with every database but can be quite slow, except on mysql, where this |
280 | with every database but can be quite slow, except on mysql, where this |
262 | should be quite fast. |
281 | should be quite fast. |
263 | |
282 | |
264 | C<sql_uexists> is similar to C<sql_exists> but upgrades all parameters to |
283 | C<sql_uexists> is similar to C<sql_exists> but upgrades all parameters to |
265 | utf8. |
284 | UTF-8. |
266 | |
285 | |
267 | Examples: |
286 | Examples: |
268 | |
287 | |
269 | print "user 7 exists!\n" |
288 | print "user 7 exists!\n" |
270 | if sql_exists "user where id = ?", 7; |
289 | if sql_exists "user where id = ?", 7; |
… | |
… | |
279 | Returns the last automatically created key value. It must be executed |
298 | Returns the last automatically created key value. It must be executed |
280 | directly after executing the insert statement that created it. This is |
299 | directly after executing the insert statement that created it. This is |
281 | what is actually returned for various databases. If your database is |
300 | what is actually returned for various databases. If your database is |
282 | missing, please send me an e-mail on how to implement this ;) |
301 | missing, please send me an e-mail on how to implement this ;) |
283 | |
302 | |
|
|
303 | mariadb: first C<AUTO_INCREMENT> column set to NULL |
284 | mysql: first C<AUTO_INCREMENT> column set to NULL |
304 | mysql: first C<AUTO_INCREMENT> column set to NULL |
285 | postgres: C<oid> column (is there a way to get the last SERIAL?) |
305 | postgres: C<oid> column (is there a way to get the last SERIAL?) |
286 | sybase: C<IDENTITY> column of the last insert (slow) |
306 | sybase: C<IDENTITY> column of the last insert (slow) |
287 | informix: C<SERIAL> or C<SERIAL8> column of the last insert |
307 | informix: C<SERIAL> or C<SERIAL8> column of the last insert |
|
|
308 | sqlite: C<last_insert_rowid()> |
288 | |
309 | |
289 | Except for sybase, this does not require a server access. |
310 | Except for sybase, this does not require a server access. |
290 | |
311 | |
291 | =cut |
312 | =cut |
292 | |
313 | |
293 | sub sql_insertid($) { |
314 | sub sql_insertid($) { |
294 | my $sth = shift or die "sql_insertid requires a statement handle"; |
315 | my $sth = shift or Carp::croak "sql_insertid requires a statement handle"; |
295 | my $dbh = $sth->{Database}; |
316 | my $dbh = $sth->{Database}; |
296 | my $driver = $dbh->{Driver}{Name}; |
317 | my $driver = $dbh->{Driver}{Name}; |
297 | |
318 | |
|
|
319 | $driver eq "MariaDB" and return $sth->{mariadb_insertid}; |
298 | $driver eq "mysql" and return $sth->{mysql_insertid}; |
320 | $driver eq "mysql" and return $sth->{mysql_insertid}; |
299 | $driver eq "Pg" and return $sth->{pg_oid_status}; |
321 | $driver eq "Pg" and return $sth->{pg_oid_status}; |
300 | $driver eq "Sybase" and return sql_fetch($dbh, 'SELECT @@IDENTITY'); |
322 | $driver eq "Sybase" and return sql_fetch ($dbh, 'SELECT @@IDENTITY'); |
301 | $driver eq "Informix" and return $sth->{ix_sqlerrd}[1]; |
323 | $driver eq "Informix" and return $sth->{ix_sqlerrd}[1]; |
|
|
324 | $driver eq "SQLite" and return sql_fetch ($dbh, 'SELECT last_insert_rowid ()'); |
302 | |
325 | |
303 | die "sql_insertid does not spport the dbd driver '$driver', please see PApp::SQL::sql_insertid"; |
326 | $dbh->last_insert_id (undef, undef, undef, undef) |
304 | } |
327 | } |
305 | |
328 | |
306 | =item [old-size] = cachesize [new-size] |
329 | =item [old-size] = cachesize [new-size] |
307 | |
330 | |
308 | Returns (and possibly changes) the LRU cache size used by C<sql_exec>. The |
331 | Returns (and possibly changes) the LRU cache size used by C<sql_exec>. The |
309 | default is somewhere around 50 (= the 50 last recently used statements |
332 | default is somewhere around 50 (= the 50 last recently used statements |
310 | will be cached). It shouldn't be too large, since a simple linear listed |
333 | will be cached). It shouldn't be too large, since a simple linear list |
311 | is used for the cache at the moment (which, for small (<100) cache sizes |
334 | is used for the cache at the moment (which, for small (<100) cache sizes |
312 | is actually quite fast). |
335 | is actually quite fast). |
313 | |
336 | |
314 | The function always returns the cache size in effect I<before> the call, |
337 | The function always returns the cache size in effect I<before> the call, |
315 | so, to nuke the cache (for example, when a database connection has died |
338 | so, to nuke the cache (for example, when a database connection has died |
… | |
… | |
340 | |
363 | |
341 | =cut |
364 | =cut |
342 | |
365 | |
343 | reinitialize; |
366 | reinitialize; |
344 | |
367 | |
|
|
368 | =head2 Type Deduction |
|
|
369 | |
|
|
370 | Since every database driver seems to deduce parameter types differently, |
|
|
371 | usually wrongly, and at leats in the case of DBD::mysql, different in |
|
|
372 | every other release or so, and this can and does lead to data corruption, |
|
|
373 | this module does type deduction itself. |
|
|
374 | |
|
|
375 | What does it mean? Simple - sql parameters for placeholders will be |
|
|
376 | explicitly marked as SQL_VARCHAR, SQL_INTEGER or SQL_DOUBLE the first time |
|
|
377 | a statement is prepared. |
|
|
378 | |
|
|
379 | To force a specific type, you can either continue to use e.g. sql casts, |
|
|
380 | or you can make sure to consistently use strings or numbers. To make a |
|
|
381 | perl scalar look enough like a string or a number, use this when passing |
|
|
382 | it to sql_exec or a similar functions: |
|
|
383 | |
|
|
384 | "$string" # to pass a string |
|
|
385 | $num+0 # to pass a number |
|
|
386 | |
|
|
387 | =cut |
|
|
388 | |
345 | package PApp::SQL::Database; |
389 | package PApp::SQL::Database; |
346 | |
390 | |
347 | =head2 THE DATABASE CLASS |
391 | =head2 The Database Class |
348 | |
392 | |
349 | Again (sigh) the problem of persistency. What do you do when you have |
393 | Again (sigh) the problem of persistency. What do you do when you have |
350 | to serialize on object that contains (or should contain) a database |
394 | to serialize on object that contains (or should contain) a database |
351 | handle? Short answer: you don't. Long answer: you can embed the necessary |
395 | handle? Short answer: you don't. Long answer: you can embed the necessary |
352 | information to recreate the dbh when needed. |
396 | information to recreate the dbh when needed. |
… | |
… | |
390 | |
434 | |
391 | sub checked_dbh($) { |
435 | sub checked_dbh($) { |
392 | my $dbh = $dbcache{$_[0][0]}; |
436 | my $dbh = $dbcache{$_[0][0]}; |
393 | $dbh && $dbh->ping |
437 | $dbh && $dbh->ping |
394 | ? $dbh |
438 | ? $dbh |
395 | : PApp::SQL::connect_cached((split /\x00/, $_[0][0]), $_[0][1], $_[0][2]); |
439 | : PApp::SQL::connect_cached((split /\x00/, $_[0][0], 4), $_[0][1], $_[0][2]); |
396 | } |
440 | } |
397 | |
441 | |
398 | =item $db->dsn |
442 | =item $db->dsn |
399 | |
443 | |
400 | Return the DSN (L<DBI>) fo the database object (e.g. for error messages). |
444 | Return the DSN (L<DBI>) fo the database object (e.g. for error messages). |
… | |
… | |
403 | |
447 | |
404 | Return the login name. |
448 | Return the login name. |
405 | |
449 | |
406 | =item $db->password |
450 | =item $db->password |
407 | |
451 | |
408 | Return the password (emphasizing the fact that the apssword is stored plaintext ;) |
452 | Return the password (emphasizing the fact that the password is stored plaintext ;) |
409 | |
453 | |
410 | =cut |
454 | =cut |
411 | |
455 | |
412 | sub dsn($) { |
456 | sub dsn($) { |
413 | my $self = shift; |
457 | my $self = shift; |
… | |
… | |
434 | |
478 | |
435 | L<PApp>. |
479 | L<PApp>. |
436 | |
480 | |
437 | =head1 AUTHOR |
481 | =head1 AUTHOR |
438 | |
482 | |
439 | Marc Lehmann <pcg@goof.com> |
483 | Marc Lehmann <schmorp@schmorp.de> |
440 | http://www.goof.com/pcg/marc/ |
484 | http://home.schmorp.de/ |
441 | |
485 | |
442 | =cut |
486 | =cut |
443 | |
487 | |