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
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, @_);
40 if (0 == scalar(@_)) {
41 $dbh->do($query) || $form->dberror($query);
43 $dbh->do($query, undef, @_) ||
44 $form->dberror($query . " (" . join(", ", @_) . ")");
47 $main::lxdebug->leave_sub(2);
50 sub selectrow_query { &selectfirst_array_query }
53 $main::lxdebug->enter_sub(2);
55 my ($form, $sth, $query) = splice(@_, 0, 3);
57 dump_query(LXDebug::QUERY, '', $query, @_);
59 if (0 == scalar(@_)) {
60 $sth->execute() || $form->dberror($query);
63 $form->dberror($query . " (" . join(", ", @_) . ")");
66 $main::lxdebug->leave_sub(2);
70 my ($level, $msg, $query) = splice(@_, 0, 3);
72 my $filename = $self_filename = 'SL/DBUtils.pm';
74 while ($filename eq $self_filename) {
75 (undef, $filename, $line, $subroutine) = caller $caller_level++;
78 while ($query =~ /\?/) {
79 my $value = shift(@_);
80 $value =~ s/\'/\\\'/g;
81 $value = "'${value}'";
82 $query =~ s/\?/$value/;
85 $query =~ s/[\n\s]+/ /g;
87 $msg .= " " if ($msg);
89 my $info = "$subroutine called from $filename:$line\n";
91 $main::lxdebug->message($level, $info . $msg . $query);
97 return "NULL" unless defined $str;
98 return "current_date" if $str =~ /current_date/;
105 $main::lxdebug->enter_sub(2);
107 my ($form, $dbh, $query) = splice(@_, 0, 3);
109 dump_query(LXDebug::QUERY, '', $query, @_);
111 my $sth = $dbh->prepare($query) || $form->dberror($query);
113 $main::lxdebug->leave_sub(2);
118 sub prepare_execute_query {
119 $main::lxdebug->enter_sub(2);
121 my ($form, $dbh, $query) = splice(@_, 0, 3);
123 dump_query(LXDebug::QUERY, '', $query, @_);
125 my $sth = $dbh->prepare($query) || $form->dberror($query);
126 if (scalar(@_) != 0) {
127 $sth->execute(@_) || $form->dberror($query . " (" . join(", ", @_) . ")");
129 $sth->execute() || $form->dberror($query);
132 $main::lxdebug->leave_sub(2);
137 sub selectall_hashref_query {
138 $main::lxdebug->enter_sub(2);
140 my ($form, $dbh, $query) = splice(@_, 0, 3);
142 my $sth = prepare_execute_query($form, $dbh, $query, @_);
144 while (my $ref = $sth->fetchrow_hashref()) {
145 push(@{ $result }, $ref);
149 $main::lxdebug->leave_sub(2);
151 return wantarray ? @{ $result } : $result;
154 sub selectall_array_query {
155 $main::lxdebug->enter_sub(2);
157 my ($form, $dbh, $query) = splice(@_, 0, 3);
159 my $sth = prepare_execute_query($form, $dbh, $query, @_);
161 while (my ($value) = $sth->fetchrow_array()) {
162 push(@result, $value);
166 $main::lxdebug->leave_sub(2);
171 sub selectfirst_hashref_query {
172 $main::lxdebug->enter_sub(2);
174 my ($form, $dbh, $query) = splice(@_, 0, 3);
176 my $sth = prepare_execute_query($form, $dbh, $query, @_);
177 my $ref = $sth->fetchrow_hashref();
180 $main::lxdebug->leave_sub(2);
185 sub selectfirst_array_query {
186 $main::lxdebug->enter_sub(2);
188 my ($form, $dbh, $query) = splice(@_, 0, 3);
190 my $sth = prepare_execute_query($form, $dbh, $query, @_);
191 my @ret = $sth->fetchrow_array();
194 $main::lxdebug->leave_sub(2);
199 sub selectall_as_map {
200 $main::lxdebug->enter_sub(2);
202 my ($form, $dbh, $query, $key_col, $value_col) = splice(@_, 0, 5);
204 my $sth = prepare_execute_query($form, $dbh, $query, @_);
207 if ('' eq ref $value_col) {
208 while (my $ref = $sth->fetchrow_hashref()) {
209 $hash{$ref->{$key_col}} = $ref->{$value_col};
212 while (my $ref = $sth->fetchrow_hashref()) {
213 $hash{$ref->{$key_col}} = { map { $_ => $ref->{$_} } @{ $value_col } };
219 $main::lxdebug->leave_sub(2);
224 sub create_sort_spec {
225 $main::lxdebug->enter_sub(2);
230 $params{defs} || die;
231 $params{default} || die;
233 # The definition of valid columns to sort by.
234 my $defs = $params{defs};
236 # The column name to sort by. Use the default column name if none was given.
237 my %result = ( 'column' => $params{column} || $params{default} );
239 # Overwrite the column name with the default column name if the other one is not valid.
240 $result{column} = $params{default} unless ($defs->{ $result{column} });
242 # The sort direction. true means 'sort ascending', false means 'sort descending'.
243 $result{dir} = defined $params{dir} ? $params{dir}
244 : defined $params{default_dir} ? $params{default_dir}
246 $result{dir} = $result{dir} ? 1 : 0;
247 my $asc_desc = $result{dir} ? 'ASC' : 'DESC';
249 # Create the SQL code.
250 my $cols = $defs->{ $result{column} };
251 $result{sql} = join ', ', map { "${_} ${asc_desc}" } @{ ref $cols eq 'ARRAY' ? $cols : [ $cols ] };
253 $main::lxdebug->leave_sub(2);
265 SL::DBUTils.pm: All about Databaseconections in Lx
271 conv_i($str, $default)
276 do_query($form, $dbh, $query)
277 do_statement($form, $sth, $query)
279 dump_query($level, $msg, $query)
280 prepare_execute_query($form, $dbh, $query)
282 my $all_results_ref = selectall_hashref_query($form, $dbh, $query)
283 my $first_result_hash_ref = selectfirst_hashref_query($form, $dbh, $query);
285 my @first_result = selectfirst_array_query($form, $dbh, $query); # ==
286 my @first_result = selectrow_query($form, $dbh, $query);
288 my %sort_spec = create_sort_spec(%params);
292 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.
294 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.
296 DBUtils relies heavily on two parameters which have to be passed to almost every function: $form and $dbh.
297 - $form is used for error handling only. It can be omitted in theory, but should not.
298 - $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!
301 Every function here should accomplish the follwing things:
302 - Easy debugging. Every handled query gets dumped via LXDebug, if specified there.
303 - Safe value binding. Although DBI is far from perfect in terms of binding, the rest of the bindings should happen here.
304 - Error handling. Should a query fail, an error message will be generated here instead of in the backend code invoking DBUtils.
306 Note that binding is not perfect here either...
308 =head2 QUOTING FUNCTIONS
314 =item conv_i STR,DEFAULT
316 Converts STR to an integer. If STR is empty, returns DEFAULT. If no DEFAULT is given, returns undef.
320 Converts STR to a date string. If STR is emptry, returns undef.
324 Database version of conv_date. Quotes STR before returning. Returns 'NULL' if STR is empty.
326 =item quote_db_date STR
328 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.
329 Returns 'NULL' if STR is empty.
333 =head2 QUERY FUNCTIONS
337 =item do_query FORM,DBH,QUERY,ARRAY
339 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.
341 =item do_statement FORM,STH,QUERY,ARRAY
343 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.
345 =item prepare_execute_query FORM,DBH,QUERY,ARRAY
347 Prepares and executes QUERY on DBH using DBI::prepare and DBI::execute. ARRAY is passed as binding values to execute.
351 =head2 RETRIEVAL FUNCTIONS
355 =item selectfirst_array_query FORM,DBH,QUERY,ARRAY
357 =item selectrow_query FORM,DBH,QUERY,ARRAY
359 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.
361 =item selectfirst_hashref_query FORM,DBH,QUERY,ARRAY
363 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.
365 =item selectall_hashref_query FORM,DBH,QUERY,ARRAY
367 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.
369 =item selectall_as_map FORM,DBH,QUERY,KEY_COL,VALUE_COL,ARRAY
371 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.
375 =head2 UTILITY FUNCTIONS
379 =item create_sort_spec
382 defs => { }, # mandatory
383 default => 'name', # mandatory
393 This function simplifies the creation of SQL code for sorting
394 columns. It uses a hashref of valid column names, the column name and
395 direction requested by the user, the application defaults for the
396 column name and the direction and returns the actual column name,
397 direction and SQL code that can be used directly in a query.
399 The parameter 'defs' is a hash reference. The keys are the column
400 names as they may come from the application. The values are either
401 scalars with SQL code or array references of SQL code. Example:
403 'defs' => { 'customername' => 'lower(customer.name)',
404 'address' => [ 'lower(customer.city)', 'lower(customer.street)' ], }
406 'default' is the default column name to sort by. It must be a key of
407 'defs' and should not be come from user input.
409 The 'column' parameter is the column name as requested by the
410 application (e.g. if the user clicked on a column header in a
411 report). If it is invalid then the 'default' parameter will be used
414 'default_dir' is the default sort direction. A true value means 'sort
415 ascending', a false one 'sort descending'. 'default_dir' defaults to
418 The 'dir' parameter is the sort direction as requested by the
419 application (e.g. if the user clicked on a column header in a
420 report). If it is undefined then the 'default_dir' parameter will be
425 =head2 DEBUG FUNCTIONS
429 =item dump_query LEVEL,MSG,QUERY,ARRAY
431 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.
439 =item Retrieving a whole table:
441 $query = qq|SELECT id, pricegroup FROM pricegroup|;
442 $form->{PRICEGROUPS} = selectall_hashref_query($form, $dbh, $query);
444 =item Retrieving a single value:
446 $query = qq|SELECT nextval('glid')|;
447 ($new_id) = selectrow_query($form, $dbh, $query);
449 =item Using binding values:
451 $query = qq|UPDATE ar SET paid = amount + paid, storno = 't' WHERE id = ?|;
452 do_query($form, $dbh, $query, $id);
454 =item A more complicated example, using dynamic binding values:
458 if ($form->{language_values} ne "") {
459 $query = qq|SELECT l.id, l.description, tr.translation, tr.longdescription
461 LEFT OUTER JOIN translation tr ON (tr.language_id = l.id) AND (tr.parts_id = ?)|;
462 @values = (conv_i($form->{id}));
464 $query = qq|SELECT id, description FROM language|;
467 my $languages = selectall_hashref_query($form, $dbh, $query, @values);
473 =head1 MODULE AUTHORS
475 Moritz Bunkus E<lt>m.bunkus@linet-services.deE<gt>
476 Sven Schoeling E<lt>s.schoeling@linet-services.deE<gt>
478 =head1 DOCUMENTATION AUTHORS
480 Udo Spallek E<lt>udono@gmx.netE<gt>
481 Sven Schoeling E<lt>s.schoeling@linet-services.deE<gt>
483 =head1 COPYRIGHT AND LICENSE
485 Copyright 2007 by Lx-Office Community
487 This program is free software; you can redistribute it and/or modify
488 it under the terms of the GNU General Public License as published by
489 the Free Software Foundation; either version 2 of the License, or
490 (at your option) any later version.
492 This program is distributed in the hope that it will be useful,
493 but WITHOUT ANY WARRANTY; without even the implied warranty of
494 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
495 GNU General Public License for more details.
496 You should have received a copy of the GNU General Public License
497 along with this program; if not, write to the Free Software
498 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.