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);
14 my ($value, $default) = @_;
15 return (defined($value) && "$value" ne "") ? $value * 1 : $default;
20 return (defined($value) && "$value" ne "") ? $value : undef;
25 if (defined($value) && "$value" ne "") {
26 $value =~ s/\'/\'\'/g;
33 $main::lxdebug->enter_sub(2);
35 my ($form, $dbh, $query) = splice(@_, 0, 3);
37 dump_query(LXDebug::QUERY, '', $query, @_);
39 if (0 == scalar(@_)) {
40 $dbh->do($query) || $form->dberror($query);
42 $dbh->do($query, undef, @_) ||
43 $form->dberror($query . " (" . join(", ", @_) . ")");
46 $main::lxdebug->leave_sub(2);
49 sub selectrow_query { &selectfirst_array_query }
52 $main::lxdebug->enter_sub(2);
54 my ($form, $sth, $query) = splice(@_, 0, 3);
56 dump_query(LXDebug::QUERY, '', $query, @_);
58 if (0 == scalar(@_)) {
59 $sth->execute() || $form->dberror($query);
62 $form->dberror($query . " (" . join(", ", @_) . ")");
65 $main::lxdebug->leave_sub(2);
69 my ($level, $msg, $query) = splice(@_, 0, 3);
71 my $filename = $self_filename = 'SL/DBUtils.pm';
73 while ($filename eq $self_filename) {
74 (undef, $filename, $line, $subroutine) = caller $caller_level++;
77 while ($query =~ /\?/) {
78 my $value = shift(@_);
79 $value =~ s/\'/\\\'/g;
80 $value = "'${value}'";
81 $query =~ s/\?/$value/;
84 $query =~ s/[\n\s]+/ /g;
86 $msg .= " " if ($msg);
88 my $info = "$subroutine called from $filename:$line\n";
90 $main::lxdebug->message($level, $info . $msg . $query);
96 return "NULL" unless defined $str;
97 return "current_date" if $str =~ /current_date/;
104 $main::lxdebug->enter_sub(2);
106 my ($form, $dbh, $query) = splice(@_, 0, 3);
108 dump_query(LXDebug::QUERY, '', $query, @_);
110 my $sth = $dbh->prepare($query) || $form->dberror($query);
112 $main::lxdebug->leave_sub(2);
117 sub prepare_execute_query {
118 $main::lxdebug->enter_sub(2);
120 my ($form, $dbh, $query) = splice(@_, 0, 3);
122 dump_query(LXDebug::QUERY, '', $query, @_);
124 my $sth = $dbh->prepare($query) || $form->dberror($query);
125 if (scalar(@_) != 0) {
126 $sth->execute(@_) || $form->dberror($query . " (" . join(", ", @_) . ")");
128 $sth->execute() || $form->dberror($query);
131 $main::lxdebug->leave_sub(2);
136 sub selectall_hashref_query {
137 $main::lxdebug->enter_sub(2);
139 my ($form, $dbh, $query) = splice(@_, 0, 3);
141 my $sth = prepare_execute_query($form, $dbh, $query, @_);
143 while (my $ref = $sth->fetchrow_hashref()) {
144 push(@{ $result }, $ref);
148 $main::lxdebug->leave_sub(2);
150 return wantarray ? @{ $result } : $result;
153 sub selectall_array_query {
154 $main::lxdebug->enter_sub(2);
156 my ($form, $dbh, $query) = splice(@_, 0, 3);
158 my $sth = prepare_execute_query($form, $dbh, $query, @_);
160 while (my ($value) = $sth->fetchrow_array()) {
161 push(@result, $value);
165 $main::lxdebug->leave_sub(2);
170 sub selectfirst_hashref_query {
171 $main::lxdebug->enter_sub(2);
173 my ($form, $dbh, $query) = splice(@_, 0, 3);
175 my $sth = prepare_execute_query($form, $dbh, $query, @_);
176 my $ref = $sth->fetchrow_hashref();
179 $main::lxdebug->leave_sub(2);
184 sub selectfirst_array_query {
185 $main::lxdebug->enter_sub(2);
187 my ($form, $dbh, $query) = splice(@_, 0, 3);
189 my $sth = prepare_execute_query($form, $dbh, $query, @_);
190 my @ret = $sth->fetchrow_array();
193 $main::lxdebug->leave_sub(2);
198 sub selectall_as_map {
199 $main::lxdebug->enter_sub(2);
201 my ($form, $dbh, $query, $key_col, $value_col) = splice(@_, 0, 5);
203 my $sth = prepare_execute_query($form, $dbh, $query, @_);
206 if ('' eq ref $value_col) {
207 while (my $ref = $sth->fetchrow_hashref()) {
208 $hash{$ref->{$key_col}} = $ref->{$value_col};
211 while (my $ref = $sth->fetchrow_hashref()) {
212 $hash{$ref->{$key_col}} = { map { $_ => $ref->{$_} } @{ $value_col } };
218 $main::lxdebug->leave_sub(2);
230 SL::DBUTils.pm: All about Databaseconections in Lx
236 conv_i($str, $default)
241 do_query($form, $dbh, $query)
242 do_statement($form, $sth, $query)
244 dump_query($level, $msg, $query)
245 prepare_execute_query($form, $dbh, $query)
247 my $all_results_ref = selectall_hashref_query($form, $dbh, $query)
248 my $first_result_hash_ref = selectfirst_hashref_query($form, $dbh, $query);
250 my @first_result = selectfirst_array_query($form, $dbh, $query); # ==
251 my @first_result = selectrow_query($form, $dbh, $query);
256 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.
258 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.
260 DBUtils relies heavily on two parameters which have to be passed to almost every function: $form and $dbh.
261 - $form is used for error handling only. It can be omitted in theory, but should not.
262 - $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!
265 Every function here should accomplish the follwing things:
266 - Easy debugging. Every handled query gets dumped via LXDebug, if specified there.
267 - Safe value binding. Although DBI is far from perfect in terms of binding, the rest of the bindings should happen here.
268 - Error handling. Should a query fail, an error message will be generated here instead of in the backend code invoking DBUtils.
270 Note that binding is not perfect here either...
272 =head2 QUOTING FUNCTIONS
278 =item conv_i STR,DEFAULT
280 Converts STR to an integer. If STR is empty, returns DEFAULT. If no DEFAULT is given, returns undef.
284 Converts STR to a date string. If STR is emptry, returns undef.
288 Database version of conv_date. Quotes STR before returning. Returns 'NULL' if STR is empty.
290 =item quote_db_date STR
292 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.
293 Returns 'NULL' if STR is empty.
297 =head2 QUERY FUNCTIONS
301 =item do_query FORM,DBH,QUERY,ARRAY
303 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.
305 =item do_statement FORM,STH,QUERY,ARRAY
307 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.
309 =item prepare_execute_query FORM,DBH,QUERY,ARRAY
311 Prepares and executes QUERY on DBH using DBI::prepare and DBI::execute. ARRAY is passed as binding values to execute.
315 =head2 RETRIEVAL FUNCTIONS
319 =item selectfirst_array_query FORM,DBH,QUERY,ARRAY
321 =item selectrow_query FORM,DBH,QUERY,ARRAY
323 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.
325 =item selectfirst_hashref_query FORM,DBH,QUERY,ARRAY
327 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.
329 =item selectall_hashref_query FORM,DBH,QUERY,ARRAY
331 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.
333 =item selectall_as_map FORM,DBH,QUERY,KEY_COL,VALUE_COL,ARRAY
335 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.
339 =head2 DEBUG FUNCTIONS
343 =item dump_query LEVEL,MSG,QUERY,ARRAY
345 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.
353 =item Retrieving a whole table:
355 $query = qq|SELECT id, pricegroup FROM pricegroup|;
356 $form->{PRICEGROUPS} = selectall_hashref_query($form, $dbh, $query);
358 =item Retrieving a single value:
360 $query = qq|SELECT nextval('glid')|;
361 ($new_id) = selectrow_query($form, $dbh, $query);
363 =item Using binding values:
365 $query = qq|UPDATE ar SET paid = amount + paid, storno = 't' WHERE id = ?|;
366 do_query($form, $dbh, $query, $id);
368 =item A more complicated example, using dynamic binding values:
372 if ($form->{language_values} ne "") {
373 $query = qq|SELECT l.id, l.description, tr.translation, tr.longdescription
375 LEFT OUTER JOIN translation tr ON (tr.language_id = l.id) AND (tr.parts_id = ?)|;
376 @values = (conv_i($form->{id}));
378 $query = qq|SELECT id, description FROM language|;
381 my $languages = selectall_hashref_query($form, $dbh, $query, @values);
387 =head1 MODULE AUTHORS
389 Moritz Bunkus E<lt>m.bunkus@linet-services.deE<gt>
390 Sven Schoeling E<lt>s.schoeling@linet-services.deE<gt>
392 =head1 DOCUMENTATION AUTHORS
394 Udo Spallek E<lt>udono@gmx.netE<gt>
395 Sven Schoeling E<lt>s.schoeling@linet-services.deE<gt>
397 =head1 COPYRIGHT AND LICENSE
399 Copyright 2007 by Lx-Office Community
401 This program is free software; you can redistribute it and/or modify
402 it under the terms of the GNU General Public License as published by
403 the Free Software Foundation; either version 2 of the License, or
404 (at your option) any later version.
406 This program is distributed in the hope that it will be useful,
407 but WITHOUT ANY WARRANTY; without even the implied warranty of
408 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
409 GNU General Public License for more details.
410 You should have received a copy of the GNU General Public License
411 along with this program; if not, write to the Free Software
412 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.