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 | |
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 | |
… | |
… | |
39 | |
39 | |
40 | =cut |
40 | =cut |
41 | |
41 | |
42 | package PApp::SQL; |
42 | package PApp::SQL; |
43 | |
43 | |
|
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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 = 0.124; |
50 | $VERSION = '2.0'; |
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 | |
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62 | boot2 DBI::SQL_VARCHAR, DBI::SQL_INTEGER, DBI::SQL_DOUBLE; |
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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. |
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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 | |
123 | Examples: |
125 | Examples: |
124 | |
126 | |
125 | # try your luck opening the papp database without access info |
127 | # try your luck opening the papp database without access info |
126 | $dbh = connect_cached __FILE__, "DBI:mysql:papp"; |
128 | $dbh = connect_cached __FILE__, "DBI:mysql:papp"; |
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129 | |
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130 | Mysql-specific behaviour: The default setting of |
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131 | C<mysql_client_found_rows> is TRUE, you can overwrite this, though. |
127 | |
132 | |
128 | =cut |
133 | =cut |
129 | |
134 | |
130 | sub connect_cached { |
135 | sub connect_cached { |
131 | my ($id, $dsn, $user, $pass, $flags, $connect) = @_; |
136 | my ($id, $dsn, $user, $pass, $flags, $connect) = @_; |
132 | # the following line is duplicated in PApp::SQL::Database::new |
137 | # the following line is duplicated in PApp::SQL::Database::new |
133 | $id = "$id\0$dsn\0$user\0$pass"; |
138 | $id = "$id\0$dsn\0$user\0$pass"; |
134 | unless ($dbcache{$id} && $dbcache{$id}->ping) { |
139 | unless ($dbcache{$id} && $dbcache{$id}->ping) { |
135 | #warn "connecting to ($dsn|$user|$pass|$flags)\n";#d# |
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136 | # first, nuke our statement cache (sooory ;) |
140 | # first, nuke our statement cache (sooory ;) |
137 | cachesize cachesize 0; |
141 | cachesize cachesize 0; |
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142 | |
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143 | # then make mysql behave more standardly by default |
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144 | $dsn =~ /^[Dd][Bb][Ii]:mysql:/ |
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145 | and $dsn !~ /;mysql_client_found_rows/ |
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146 | and $dsn .= ";mysql_client_found_rows=1"; |
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147 | |
138 | # then connect anew |
148 | # then connect anew |
139 | $dbcache{$id} = |
149 | $dbcache{$id} = |
140 | eval { DBI->connect($dsn, $user, $pass, $flags) } |
150 | eval { DBI->connect($dsn, $user, $pass, $flags) } |
141 | || eval { DBI->connect($dsn, $user, $pass, $flags) } |
151 | || eval { DBI->connect($dsn, $user, $pass, $flags) } |
142 | || die "unable to connect to database $dsn: $DBI::errstr\n"; |
152 | || Carp::croak "unable to connect to database $dsn: $DBI::errstr\n"; |
143 | $connect->($dbcache{$id}) if $connect; |
153 | $connect->($dbcache{$id}) if $connect; |
144 | } |
154 | } |
145 | $dbcache{$id}; |
155 | $dbcache{$id}; |
146 | } |
156 | } |
147 | |
157 | |
… | |
… | |
155 | statement handle. The command and the statement handle will be cached |
165 | statement handle. The command and the statement handle will be cached |
156 | (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 |
157 | 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 |
158 | 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> |
159 | 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 |
160 | 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 |
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171 | anymore, as the subsequent call will re-use the handle. |
161 | |
172 | |
162 | 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, |
163 | 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 |
164 | calling) package and, if that fails, it tries to use database handle in |
175 | before calling these functions. NOTICE: future and former versions of |
165 | 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 |
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177 | package. |
166 | |
178 | |
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179 | =begin comment |
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180 | |
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181 | If it is missing, C<sql_exec> first tries to use the variable C<$DBH> |
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182 | in the current (= calling) package and, if that fails, it tries to use |
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183 | database handle in C<$PApp::SQL::DBH>, which you can set before calling |
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184 | these functions. |
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185 | |
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186 | =end comment |
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187 | |
167 | The actual return value from the C<$sth->execute> call is stored in the |
188 | The actual return value from the C<< $sth->execute >> call is stored in |
168 | package-global (and exported) variable C<$sql_exec>. |
189 | the package-global (and exported) variable C<$sql_exec>. |
169 | |
190 | |
170 | If any error occurs C<sql_exec> will throw an exception. |
191 | If any error occurs C<sql_exec> will throw an exception. |
171 | |
192 | |
172 | 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 |
173 | utf8 before calling the C<execute> method. |
194 | UTF-8 before calling the C<execute> method. |
174 | |
195 | |
175 | Examples: |
196 | Examples: |
176 | |
197 | |
177 | # easy one |
198 | # easy one |
178 | my $st = sql_exec "select name, id from table where id = ?", $id; |
199 | my $st = sql_exec "select name, id from table where id = ?", $id; |
… | |
… | |
212 | my($name, $amount) = sql_fetch "select ...", args... |
233 | my($name, $amount) = sql_fetch "select ...", args... |
213 | |
234 | |
214 | ... and it's still quite fast unless you fetch large amounts of data. |
235 | ... and it's still quite fast unless you fetch large amounts of data. |
215 | |
236 | |
216 | C<sql_ufetch> is similar to C<sql_fetch> but upgrades all input values to |
237 | C<sql_ufetch> is similar to C<sql_fetch> but upgrades all input values to |
217 | utf8 and forces all result values to utf8. |
238 | UTF-8 and forces all result values to UTF-8 (this does I<not> include result |
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239 | parameters, only return values. Using bind variables in conjunction with |
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240 | sql_u* functions might result in undefined behaviour - we use UTF-8 on |
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241 | bind-variables at execution time and it seems to work on DBD::mysql as it |
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242 | ignores the UTF-8 bit completely. Which just means that that DBD-driver is |
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243 | broken). |
218 | |
244 | |
219 | =item sql_fetchall <see sql_exec> |
245 | =item sql_fetchall <see sql_exec> |
220 | |
246 | |
221 | =item sql_ufetchall <see sql_uexec> |
247 | =item sql_ufetchall <see sql_uexec> |
222 | |
248 | |
… | |
… | |
239 | for (sql_fetchall "select name, age, place from user") { |
265 | for (sql_fetchall "select name, age, place from user") { |
240 | my ($name, $age, $place) = @$_; |
266 | my ($name, $age, $place) = @$_; |
241 | } |
267 | } |
242 | |
268 | |
243 | 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 |
244 | 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 |
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271 | the description of C<sql_ufetch>, though). |
245 | |
272 | |
246 | =item sql_exists "<table> where ...", args... |
273 | =item sql_exists "<table_references> where <where_condition>...", args... |
247 | |
274 | |
248 | =item sql_uexists <see sql_exists> |
275 | =item sql_uexists <see sql_exists> |
249 | |
276 | |
250 | Check wether the result of the sql-statement "select xxx from |
277 | Check wether the result of the sql-statement "select xxx from |
251 | $first_argument" would be empty or not (that is, imagine the string |
278 | $first_argument" would be empty or not (that is, imagine the string |
252 | "select * from" were prepended to your statement (it isn't)). Should work |
279 | "select * from" were prepended to your statement (it isn't)). Should work |
253 | with every database but can be quite slow, except on mysql, where this |
280 | with every database but can be quite slow, except on mysql, where this |
254 | should be quite fast. |
281 | should be quite fast. |
255 | |
282 | |
256 | C<sql_uexists> is similar to C<sql_exists> but upgrades all parameters to |
283 | C<sql_uexists> is similar to C<sql_exists> but upgrades all parameters to |
257 | utf8. |
284 | UTF-8. |
258 | |
285 | |
259 | Examples: |
286 | Examples: |
260 | |
287 | |
261 | print "user 7 exists!\n" |
288 | print "user 7 exists!\n" |
262 | if sql_exists "user where id = ?", 7; |
289 | if sql_exists "user where id = ?", 7; |
… | |
… | |
275 | |
302 | |
276 | mysql: first C<AUTO_INCREMENT> column set to NULL |
303 | mysql: first C<AUTO_INCREMENT> column set to NULL |
277 | postgres: C<oid> column (is there a way to get the last SERIAL?) |
304 | postgres: C<oid> column (is there a way to get the last SERIAL?) |
278 | sybase: C<IDENTITY> column of the last insert (slow) |
305 | sybase: C<IDENTITY> column of the last insert (slow) |
279 | informix: C<SERIAL> or C<SERIAL8> column of the last insert |
306 | informix: C<SERIAL> or C<SERIAL8> column of the last insert |
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307 | sqlite: C<last_insert_rowid()> |
280 | |
308 | |
281 | Except for sybase, this does not require a server access. |
309 | Except for sybase, this does not require a server access. |
282 | |
310 | |
283 | =cut |
311 | =cut |
284 | |
312 | |
285 | sub sql_insertid($) { |
313 | sub sql_insertid($) { |
286 | my $sth = shift or die "sql_insertid requires a statement handle"; |
314 | my $sth = shift or Carp::croak "sql_insertid requires a statement handle"; |
287 | my $dbh = $sth->{Database}; |
315 | my $dbh = $sth->{Database}; |
288 | my $driver = $dbh->{Driver}{Name}; |
316 | my $driver = $dbh->{Driver}{Name}; |
289 | |
317 | |
290 | $driver eq "mysql" and return $sth->{mysql_insertid}; |
318 | $driver eq "mysql" and return $sth->{mysql_insertid}; |
291 | $driver eq "Pg" and return $sth->{pg_oid_status}; |
319 | $driver eq "Pg" and return $sth->{pg_oid_status}; |
292 | $driver eq "Sybase" and return sql_fetch($dbh, 'SELECT @@IDENTITY'); |
320 | $driver eq "Sybase" and return sql_fetch ($dbh, 'SELECT @@IDENTITY'); |
293 | $driver eq "Informix" and return $sth->{ix_sqlerrd}[1]; |
321 | $driver eq "Informix" and return $sth->{ix_sqlerrd}[1]; |
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322 | $driver eq "SQLite" and return sql_fetch ($dbh, 'SELECT last_insert_rowid ()'); |
294 | |
323 | |
295 | die "sql_insertid does not spport the dbd driver '$driver', please see PApp::SQL::sql_insertid"; |
324 | Carp::croak "sql_insertid does not support the dbd driver '$driver', at"; |
296 | } |
325 | } |
297 | |
326 | |
298 | =item [old-size] = cachesize [new-size] |
327 | =item [old-size] = cachesize [new-size] |
299 | |
328 | |
300 | Returns (and possibly changes) the LRU cache size used by C<sql_exec>. The |
329 | Returns (and possibly changes) the LRU cache size used by C<sql_exec>. The |
301 | default is somewhere around 50 (= the 50 last recently used statements |
330 | default is somewhere around 50 (= the 50 last recently used statements |
302 | will be cached). It shouldn't be too large, since a simple linear listed |
331 | will be cached). It shouldn't be too large, since a simple linear list |
303 | is used for the cache at the moment (which, for small (<100) cache sizes |
332 | is used for the cache at the moment (which, for small (<100) cache sizes |
304 | is actually quite fast). |
333 | is actually quite fast). |
305 | |
334 | |
306 | The function always returns the cache size in effect I<before> the call, |
335 | The function always returns the cache size in effect I<before> the call, |
307 | so, to nuke the cache (for example, when a database connection has died |
336 | so, to nuke the cache (for example, when a database connection has died |
… | |
… | |
332 | |
361 | |
333 | =cut |
362 | =cut |
334 | |
363 | |
335 | reinitialize; |
364 | reinitialize; |
336 | |
365 | |
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366 | =head2 Type Deduction |
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367 | |
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368 | Since every database driver seems to deduce parameter types differently, |
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369 | usually wrongly, and at leats in the case of DBD::mysql, different in |
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370 | every other release or so, and this can and does lead to data corruption, |
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371 | this module does type deduction itself. |
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372 | |
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373 | What does it mean? Simple - sql parameters for placeholders will be |
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374 | explicitly marked as SQL_VARCHAR, SQL_INTEGER or SQL_DOUBLE the first time |
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375 | a statement is prepared. |
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376 | |
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377 | To force a specific type, you can either continue to use e.g. sql casts, |
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378 | or you can make sure to consistently use strings or numbers. To make a |
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379 | perl scalar look enough like a string or a number, use this when passing |
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380 | it to sql_exec or a similar functions: |
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381 | |
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382 | "$string" # to pass a string |
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383 | $num+0 # to pass a number |
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384 | |
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385 | =cut |
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386 | |
337 | package PApp::SQL::Database; |
387 | package PApp::SQL::Database; |
338 | |
388 | |
339 | =head2 THE DATABASE CLASS |
389 | =head2 The Database Class |
340 | |
390 | |
341 | Again (sigh) the problem of persistency. What do you do when you have |
391 | Again (sigh) the problem of persistency. What do you do when you have |
342 | to serialize on object that contains (or should contain) a database |
392 | to serialize on object that contains (or should contain) a database |
343 | handle? Short answer: you don't. Long answer: you can embed the necessary |
393 | handle? Short answer: you don't. Long answer: you can embed the necessary |
344 | information to recreate the dbh when needed. |
394 | information to recreate the dbh when needed. |
… | |
… | |
382 | |
432 | |
383 | sub checked_dbh($) { |
433 | sub checked_dbh($) { |
384 | my $dbh = $dbcache{$_[0][0]}; |
434 | my $dbh = $dbcache{$_[0][0]}; |
385 | $dbh && $dbh->ping |
435 | $dbh && $dbh->ping |
386 | ? $dbh |
436 | ? $dbh |
387 | : PApp::SQL::connect_cached((split /\x00/, $_[0][0]), $_[0][1], $_[0][2]); |
437 | : PApp::SQL::connect_cached((split /\x00/, $_[0][0], 4), $_[0][1], $_[0][2]); |
388 | } |
438 | } |
389 | |
439 | |
390 | =item $db->dsn |
440 | =item $db->dsn |
391 | |
441 | |
392 | Return the DSN (L<DBI>) fo the database object (e.g. for error messages). |
442 | Return the DSN (L<DBI>) fo the database object (e.g. for error messages). |
… | |
… | |
395 | |
445 | |
396 | Return the login name. |
446 | Return the login name. |
397 | |
447 | |
398 | =item $db->password |
448 | =item $db->password |
399 | |
449 | |
400 | Return the password (emphasizing the fact that the apssword is stored plaintext ;) |
450 | Return the password (emphasizing the fact that the password is stored plaintext ;) |
401 | |
451 | |
402 | =cut |
452 | =cut |
403 | |
453 | |
404 | sub dsn($) { |
454 | sub dsn($) { |
405 | my $self = shift; |
455 | my $self = shift; |
… | |
… | |
426 | |
476 | |
427 | L<PApp>. |
477 | L<PApp>. |
428 | |
478 | |
429 | =head1 AUTHOR |
479 | =head1 AUTHOR |
430 | |
480 | |
431 | Marc Lehmann <pcg@goof.com> |
481 | Marc Lehmann <schmorp@schmorp.de> |
432 | http://www.goof.com/pcg/marc/ |
482 | http://home.schmorp.de/ |
433 | |
483 | |
434 | =cut |
484 | =cut |
435 | |
485 | |