6 @EXPORT = qw(conv_i conv_date conv_dateq do_query selectrow_query do_statement
7 dump_query quote_db_date
8 selectfirst_hashref_query selectfirst_array_query
9 selectall_hashref_query selectall_array_query
11 prepare_execute_query prepare_query
12 create_sort_spec does_table_exist);
15 my ($value, $default) = @_;
16 return (defined($value) && "$value" ne "") ? $value * 1 : $default;
21 return (defined($value) && "$value" ne "") ? $value : undef;
26 if (defined($value) && "$value" ne "") {
27 $value =~ s/\'/\'\'/g;
34 $main::lxdebug->enter_sub(2);
36 my ($form, $dbh, $query) = splice(@_, 0, 3);
38 dump_query(LXDebug::QUERY, '', $query, @_);
41 if (0 == scalar(@_)) {
42 $result = $dbh->do($query) || $form->dberror($query);
44 $result = $dbh->do($query, undef, @_) || $form->dberror($query . " (" . join(", ", @_) . ")");
47 $main::lxdebug->leave_sub(2);
52 sub selectrow_query { &selectfirst_array_query }
55 $main::lxdebug->enter_sub(2);
57 my ($form, $sth, $query) = splice(@_, 0, 3);
59 dump_query(LXDebug::QUERY, '', $query, @_);
62 if (0 == scalar(@_)) {
63 $result = $sth->execute() || $form->dberror($query);
65 $result = $sth->execute(@_) || $form->dberror($query . " (" . join(", ", @_) . ")");
68 $main::lxdebug->leave_sub(2);
74 my ($level, $msg, $query) = splice(@_, 0, 3);
76 my $filename = $self_filename = 'SL/DBUtils.pm';
78 while ($filename eq $self_filename) {
79 (undef, $filename, $line, $subroutine) = caller $caller_level++;
82 while ($query =~ /\?/) {
83 my $value = shift(@_);
84 $value =~ s/\'/\\\'/g;
85 $value = "'${value}'";
86 $query =~ s/\?/$value/;
89 $query =~ s/[\n\s]+/ /g;
91 $msg .= " " if ($msg);
93 my $info = "$subroutine called from $filename:$line\n";
95 $main::lxdebug->message($level, $info . $msg . $query);
101 return "NULL" unless defined $str;
102 return "current_date" if $str =~ /current_date/;
109 $main::lxdebug->enter_sub(2);
111 my ($form, $dbh, $query) = splice(@_, 0, 3);
113 dump_query(LXDebug::QUERY, '', $query, @_);
115 my $sth = $dbh->prepare($query) || $form->dberror($query);
117 $main::lxdebug->leave_sub(2);
122 sub prepare_execute_query {
123 $main::lxdebug->enter_sub(2);
125 my ($form, $dbh, $query) = splice(@_, 0, 3);
127 dump_query(LXDebug::QUERY, '', $query, @_);
129 my $sth = $dbh->prepare($query) || $form->dberror($query);
130 if (scalar(@_) != 0) {
131 $sth->execute(@_) || $form->dberror($query . " (" . join(", ", @_) . ")");
133 $sth->execute() || $form->dberror($query);
136 $main::lxdebug->leave_sub(2);
141 sub selectall_hashref_query {
142 $main::lxdebug->enter_sub(2);
144 my ($form, $dbh, $query) = splice(@_, 0, 3);
146 my $sth = prepare_execute_query($form, $dbh, $query, @_);
148 while (my $ref = $sth->fetchrow_hashref()) {
149 push(@{ $result }, $ref);
153 $main::lxdebug->leave_sub(2);
155 return wantarray ? @{ $result } : $result;
158 sub selectall_array_query {
159 $main::lxdebug->enter_sub(2);
161 my ($form, $dbh, $query) = splice(@_, 0, 3);
163 my $sth = prepare_execute_query($form, $dbh, $query, @_);
165 while (my ($value) = $sth->fetchrow_array()) {
166 push(@result, $value);
170 $main::lxdebug->leave_sub(2);
175 sub selectfirst_hashref_query {
176 $main::lxdebug->enter_sub(2);
178 my ($form, $dbh, $query) = splice(@_, 0, 3);
180 my $sth = prepare_execute_query($form, $dbh, $query, @_);
181 my $ref = $sth->fetchrow_hashref();
184 $main::lxdebug->leave_sub(2);
189 sub selectfirst_array_query {
190 $main::lxdebug->enter_sub(2);
192 my ($form, $dbh, $query) = splice(@_, 0, 3);
194 my $sth = prepare_execute_query($form, $dbh, $query, @_);
195 my @ret = $sth->fetchrow_array();
198 $main::lxdebug->leave_sub(2);
203 sub selectall_as_map {
204 $main::lxdebug->enter_sub(2);
206 my ($form, $dbh, $query, $key_col, $value_col) = splice(@_, 0, 5);
208 my $sth = prepare_execute_query($form, $dbh, $query, @_);
211 if ('' eq ref $value_col) {
212 while (my $ref = $sth->fetchrow_hashref()) {
213 $hash{$ref->{$key_col}} = $ref->{$value_col};
216 while (my $ref = $sth->fetchrow_hashref()) {
217 $hash{$ref->{$key_col}} = { map { $_ => $ref->{$_} } @{ $value_col } };
223 $main::lxdebug->leave_sub(2);
228 sub create_sort_spec {
229 $main::lxdebug->enter_sub(2);
234 $params{defs} || die;
235 $params{default} || die;
237 # The definition of valid columns to sort by.
238 my $defs = $params{defs};
240 # The column name to sort by. Use the default column name if none was given.
241 my %result = ( 'column' => $params{column} || $params{default} );
243 # Overwrite the column name with the default column name if the other one is not valid.
244 $result{column} = $params{default} unless ($defs->{ $result{column} });
246 # The sort direction. true means 'sort ascending', false means 'sort descending'.
247 $result{dir} = defined $params{dir} ? $params{dir}
248 : defined $params{default_dir} ? $params{default_dir}
250 $result{dir} = $result{dir} ? 1 : 0;
251 my $asc_desc = $result{dir} ? 'ASC' : 'DESC';
253 # Create the SQL code.
254 my $cols = $defs->{ $result{column} };
255 $result{sql} = join ', ', map { "${_} ${asc_desc}" } @{ ref $cols eq 'ARRAY' ? $cols : [ $cols ] };
257 $main::lxdebug->leave_sub(2);
262 sub does_table_exist {
263 $main::lxdebug->enter_sub(2);
271 my $sth = $dbh->table_info('', '', $table, 'TABLE');
273 $result = $sth->fetchrow_hashref();
278 $main::lxdebug->leave_sub(2);
291 SL::DBUTils.pm: All about Databaseconections in Lx
297 conv_i($str, $default)
302 do_query($form, $dbh, $query)
303 do_statement($form, $sth, $query)
305 dump_query($level, $msg, $query)
306 prepare_execute_query($form, $dbh, $query)
308 my $all_results_ref = selectall_hashref_query($form, $dbh, $query)
309 my $first_result_hash_ref = selectfirst_hashref_query($form, $dbh, $query);
311 my @first_result = selectfirst_array_query($form, $dbh, $query); # ==
312 my @first_result = selectrow_query($form, $dbh, $query);
314 my %sort_spec = create_sort_spec(%params);
318 DBUtils is the attempt to reduce the amount of overhead it takes to retrieve information from the database in Lx-Office. Previously it would take about 15 lines of code just to get one single integer out of the database, including failure procedures and importing the necessary packages. Debugging would take even more.
320 Using DBUtils most database procedures can be reduced to defining the query, executing it, and retrieving the result. Let DBUtils handle the rest. Whenever there is a database operation not covered in DBUtils, add it here, rather than working around it in the backend code.
322 DBUtils relies heavily on two parameters which have to be passed to almost every function: $form and $dbh.
323 - $form is used for error handling only. It can be omitted in theory, but should not.
324 - $dbh is a handle to the databe, as returned by the DBI::connect routine. If you don't have an active connectiong, you can query $form->get_standard_dbh() to get a generic no_auto connection. Don't forget to commit in this case!
327 Every function here should accomplish the follwing things:
328 - Easy debugging. Every handled query gets dumped via LXDebug, if specified there.
329 - Safe value binding. Although DBI is far from perfect in terms of binding, the rest of the bindings should happen here.
330 - Error handling. Should a query fail, an error message will be generated here instead of in the backend code invoking DBUtils.
332 Note that binding is not perfect here either...
334 =head2 QUOTING FUNCTIONS
340 =item conv_i STR,DEFAULT
342 Converts STR to an integer. If STR is empty, returns DEFAULT. If no DEFAULT is given, returns undef.
346 Converts STR to a date string. If STR is emptry, returns undef.
350 Database version of conv_date. Quotes STR before returning. Returns 'NULL' if STR is empty.
352 =item quote_db_date STR
354 Treats STR as a database date, quoting it. If STR equals current_date returns an escaped version which is treated as the current date by Postgres.
355 Returns 'NULL' if STR is empty.
359 =head2 QUERY FUNCTIONS
363 =item do_query FORM,DBH,QUERY,ARRAY
365 Uses DBI::do to execute QUERY on DBH using ARRAY for binding values. FORM is only needed for error handling, but should always be passed nevertheless. Use this for insertions or updates that don't need to be prepared.
367 Returns the result of DBI::do which is -1 in case of an error and the number of affected rows otherwise.
369 =item do_statement FORM,STH,QUERY,ARRAY
371 Uses DBI::execute to execute QUERY on DBH using ARRAY for binding values. As with do_query, FORM is only used for error handling. If you are unsure what to use, refer to the documentation of DBI::do and DBI::execute.
373 Returns the result of DBI::execute which is -1 in case of an error and the number of affected rows otherwise.
375 =item prepare_execute_query FORM,DBH,QUERY,ARRAY
377 Prepares and executes QUERY on DBH using DBI::prepare and DBI::execute. ARRAY is passed as binding values to execute.
381 =head2 RETRIEVAL FUNCTIONS
385 =item selectfirst_array_query FORM,DBH,QUERY,ARRAY
387 =item selectrow_query FORM,DBH,QUERY,ARRAY
389 Prepares and executes a query using DBUtils functions, retireves the first row from the database, and returns it as an arrayref of the first row.
391 =item selectfirst_hashref_query FORM,DBH,QUERY,ARRAY
393 Prepares and executes a query using DBUtils functions, retireves the first row from the database, and returns it as a hashref of the first row.
395 =item selectall_hashref_query FORM,DBH,QUERY,ARRAY
397 Prepares and executes a query using DBUtils functions, retireves all data from the database, and returns it in hashref mode. This is slightly confusing, as the data structure will actually be a reference to an array, containing hashrefs for each row.
399 =item selectall_as_map FORM,DBH,QUERY,KEY_COL,VALUE_COL,ARRAY
401 Prepares and executes a query using DBUtils functions, retireves all data from the database, and creates a hash from the results using KEY_COL as the column for the hash keys and VALUE_COL for its values.
405 =head2 UTILITY FUNCTIONS
409 =item create_sort_spec
412 defs => { }, # mandatory
413 default => 'name', # mandatory
423 This function simplifies the creation of SQL code for sorting
424 columns. It uses a hashref of valid column names, the column name and
425 direction requested by the user, the application defaults for the
426 column name and the direction and returns the actual column name,
427 direction and SQL code that can be used directly in a query.
429 The parameter 'defs' is a hash reference. The keys are the column
430 names as they may come from the application. The values are either
431 scalars with SQL code or array references of SQL code. Example:
433 'defs' => { 'customername' => 'lower(customer.name)',
434 'address' => [ 'lower(customer.city)', 'lower(customer.street)' ], }
436 'default' is the default column name to sort by. It must be a key of
437 'defs' and should not be come from user input.
439 The 'column' parameter is the column name as requested by the
440 application (e.g. if the user clicked on a column header in a
441 report). If it is invalid then the 'default' parameter will be used
444 'default_dir' is the default sort direction. A true value means 'sort
445 ascending', a false one 'sort descending'. 'default_dir' defaults to
448 The 'dir' parameter is the sort direction as requested by the
449 application (e.g. if the user clicked on a column header in a
450 report). If it is undefined then the 'default_dir' parameter will be
455 =head2 DEBUG FUNCTIONS
459 =item dump_query LEVEL,MSG,QUERY,ARRAY
461 Dumps a query using LXDebug->message, using LEVEL for the debug-level of LXDebug. If MSG is given, it preceeds the QUERY dump in the logfiles. ARRAY is used to interpolate the '?' placeholders in QUERY, the resulting QUERY can be copy-pasted into a database frontend for debugging. Note that this method is also automatically called by each of the other QUERY FUNCTIONS, so there is in general little need to invoke it manually.
469 =item Retrieving a whole table:
471 $query = qq|SELECT id, pricegroup FROM pricegroup|;
472 $form->{PRICEGROUPS} = selectall_hashref_query($form, $dbh, $query);
474 =item Retrieving a single value:
476 $query = qq|SELECT nextval('glid')|;
477 ($new_id) = selectrow_query($form, $dbh, $query);
479 =item Using binding values:
481 $query = qq|UPDATE ar SET paid = amount + paid, storno = 't' WHERE id = ?|;
482 do_query($form, $dbh, $query, $id);
484 =item A more complicated example, using dynamic binding values:
488 if ($form->{language_values} ne "") {
489 $query = qq|SELECT l.id, l.description, tr.translation, tr.longdescription
491 LEFT OUTER JOIN translation tr ON (tr.language_id = l.id) AND (tr.parts_id = ?)|;
492 @values = (conv_i($form->{id}));
494 $query = qq|SELECT id, description FROM language|;
497 my $languages = selectall_hashref_query($form, $dbh, $query, @values);
503 =head1 MODULE AUTHORS
505 Moritz Bunkus E<lt>m.bunkus@linet-services.deE<gt>
506 Sven Schoeling E<lt>s.schoeling@linet-services.deE<gt>
508 =head1 DOCUMENTATION AUTHORS
510 Udo Spallek E<lt>udono@gmx.netE<gt>
511 Sven Schoeling E<lt>s.schoeling@linet-services.deE<gt>
513 =head1 COPYRIGHT AND LICENSE
515 Copyright 2007 by Lx-Office Community
517 This program is free software; you can redistribute it and/or modify
518 it under the terms of the GNU General Public License as published by
519 the Free Software Foundation; either version 2 of the License, or
520 (at your option) any later version.
522 This program is distributed in the hope that it will be useful,
523 but WITHOUT ANY WARRANTY; without even the implied warranty of
524 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
525 GNU General Public License for more details.
526 You should have received a copy of the GNU General Public License
527 along with this program; if not, write to the Free Software
528 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.