Annotation of loncom/interface/lonmysql.pm, revision 1.18
1.1 matthew 1: # The LearningOnline Network with CAPA
2: # MySQL utility functions
3: #
1.18 ! www 4: # $Id: lonmysql.pm,v 1.17 2003/12/27 01:44:49 www Exp $
1.1 matthew 5: #
6: # Copyright Michigan State University Board of Trustees
7: #
8: # This file is part of the LearningOnline Network with CAPA (LON-CAPA).
9: #
10: # LON-CAPA is free software; you can redistribute it and/or modify
11: # it under the terms of the GNU General Public License as published by
12: # the Free Software Foundation; either version 2 of the License, or
13: # (at your option) any later version.
14: #
15: # LON-CAPA is distributed in the hope that it will be useful,
16: # but WITHOUT ANY WARRANTY; without even the implied warranty of
17: # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18: # GNU General Public License for more details.
19: #
20: # You should have received a copy of the GNU General Public License
21: # along with LON-CAPA; if not, write to the Free Software
22: # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23: #
24: # /home/httpd/html/adm/gpl.txt
25: #
26: # http://www.lon-capa.org/
27: #
28: ######################################################################
29:
30: package Apache::lonmysql;
31:
32: use strict;
33: use DBI;
34: use Apache::lonnet();
1.16 www 35: use POSIX qw(strftime mktime);
36:
1.1 matthew 37:
38: ######################################################################
39: ######################################################################
40:
41: =pod
42:
43: =head1 Name
44:
45: lonmysql - LONCAPA MySQL utility functions
46:
47: =head1 Synopsis
48:
49: lonmysql contains utility functions to make accessing the mysql loncapa
50: database easier.
51:
52: =head1 Description
53:
54: lonmysql does its best to encapsulate all the database/table functions
55: and provide a common interface. The goal, however, is not to provide
56: a complete reimplementation of the DBI interface. Instead we try to
57: make using mysql as painless as possible.
58:
59: Each table has a numeric ID that is a parameter to most lonmysql functions.
60: The table id is returned by &create_table.
61: If you lose the table id, it is lost forever.
62: The table names in MySQL correspond to
63: $ENV{'user.name'}.'_'.$ENV{'user.domain'}.'_'.$table_id. If the table id
64: is non-numeric, it is assumed to be the full name of a table. If you pass
65: the table id in a form, you MUST ensure that what you send to lonmysql is
66: numeric, otherwise you are opening up all the tables in the MySQL database.
67:
68: =over 4
69:
70: =item Creating a table
71:
72: To create a table, you need a description of its structure. See the entry
73: for &create_table for a description of what is needed.
74:
75: $table_id = &create_table({
1.9 matthew 76: id => 'tableid', # usually you will use the returned id
77: columns => (
78: { name => 'id',
79: type => 'INT',
80: restrictions => 'NOT NULL',
81: primary_key => 'yes',
82: auto_inc => 'yes'
83: },
84: { name => 'verbage',
85: type => 'TEXT' },
86: ),
87: fulltext => [qw/verbage/],
1.3 matthew 88: });
1.1 matthew 89:
90: The above command will create a table with two columns, 'id' and 'verbage'.
91:
92: 'id' will be an integer which is autoincremented and non-null.
93:
94: 'verbage' will be of type 'TEXT', which (conceivably) allows any length
95: text string to be stored. Depending on your intentions for this database,
96: setting restrictions => 'NOT NULL' may help you avoid storing empty data.
97:
1.3 matthew 98: the fulltext element sets up the 'verbage' column for 'FULLTEXT' searching.
1.1 matthew 99:
100:
101:
102: =item Storing rows
103:
104: Storing a row in a table requires calling &store_row($table_id,$data)
105:
106: $data is either a hash reference or an array reference. If it is an array
107: reference, the data is passed as is (after being escaped) to the
108: "INSERT INTO <table> VALUES( ... )" SQL command. If $data is a hash reference,
109: the data will be placed into an array in the proper column order for the table
110: and then passed to the database.
111:
112: An example of inserting into the table created above is:
113:
114: &store_row($table_id,[undef,'I am not a crackpot!']);
115:
116: or equivalently,
117:
118: &store_row($table_id,{ verbage => 'I am not a crackpot!'});
119:
120: Since the above table was created with the first column ('id') as
121: autoincrement, providing a value is unnecessary even though the column was
122: marked as 'NOT NULL'.
123:
124:
125:
126: =item Retrieving rows
127:
128: Retrieving rows requires calling get_rows:
129:
130: @row = &Apache::lonmysql::get_rows($table_id,$condition)
131:
132: This results in the query "SELECT * FROM <table> HAVING $condition".
133:
134: @row = &Apache::lonmysql::get_rows($table_id,'id>20');
135:
136: returns all rows with column 'id' greater than 20.
137:
138: =back
139:
140: =cut
141:
142: ######################################################################
143: ######################################################################
144: =pod
145:
146: =head1 Package Variables
147:
148: =over 4
149:
150: =cut
151:
152: ##################################################
153: ##################################################
154:
155: =pod
156:
157: =item %Tables
158:
159: Holds information regarding the currently open connections. Each key
160: in the %Tables hash will be a unique table key. The value associated
161: with a key is a hash reference. Most values are initialized when the
162: table is created.
163:
164: The following entries are allowed in the hash reference:
165:
166: =over 4
167:
1.3 matthew 168: =item Name
169:
170: Table name.
171:
172: =item Type
173:
174: The type of table, typically MyISAM.
175:
176: =item Row_format
177:
178: Describes how rows should be stored in the table. DYNAMIC or STATIC.
179:
180: =item Create_time
181:
182: The date of the tables creation.
183:
184: =item Update_time
185:
186: The date of the last modification of the table.
187:
188: =item Check_time
189:
190: Usually NULL.
191:
192: =item Avg_row_length
193:
194: The average length of the rows.
195:
196: =item Data_length
197:
198: The length of the data stored in the table (bytes)
199:
200: =item Max_data_length
201:
202: The maximum possible size of the table (bytes).
1.1 matthew 203:
1.3 matthew 204: =item Index_length
1.1 matthew 205:
1.3 matthew 206: The length of the index for the table (bytes)
1.1 matthew 207:
1.3 matthew 208: =item Data_free
1.1 matthew 209:
1.3 matthew 210: I have no idea what this is.
1.1 matthew 211:
1.3 matthew 212: =item Comment
1.1 matthew 213:
1.3 matthew 214: The comment associated with the table.
215:
216: =item Rows
217:
218: The number of rows in the table.
219:
220: =item Auto_increment
221:
222: The value of the next auto_increment field.
223:
224: =item Create_options
225:
226: I have no idea.
227:
228: =item Col_order
229:
230: an array reference which holds the order of columns in the table.
231:
232: =item row_insert_sth
1.1 matthew 233:
234: The statement handler for row inserts.
235:
1.9 matthew 236: =item row_replace_sth
237:
238: The statement handler for row inserts.
239:
1.1 matthew 240: =back
241:
1.3 matthew 242: Col_order and row_insert_sth are kept internally by lonmysql and are not
243: part of the usual MySQL table information.
244:
1.1 matthew 245: =cut
246:
247: ##################################################
248: ##################################################
249: my %Tables;
250:
251: ##################################################
252: ##################################################
253: =pod
254:
255: =item $errorstring
256:
257: Holds the last error.
258:
259: =cut
260: ##################################################
261: ##################################################
262: my $errorstring;
263:
264: ##################################################
265: ##################################################
266: =pod
267:
268: =item $debugstring
269:
270: Describes current events within the package.
271:
272: =cut
273: ##################################################
274: ##################################################
275: my $debugstring;
276:
277: ##################################################
278: ##################################################
279:
280: =pod
281:
282: =item $dbh
283:
284: The database handler; The actual connection to MySQL via the perl DBI.
285:
286: =cut
287:
288: ##################################################
289: ##################################################
290: my $dbh;
291:
292: ##################################################
293: ##################################################
294:
295: # End of global variable declarations
296:
297: =pod
298:
299: =back
300:
301: =cut
302:
303: ######################################################################
304: ######################################################################
305:
306: =pod
307:
308: =head1 Internals
309:
310: =over 4
311:
312: =cut
313:
314: ######################################################################
315: ######################################################################
316:
317: =pod
318:
319: =item &connect_to_db()
320:
321: Inputs: none.
322:
323: Returns: undef on error, 1 on success.
324:
325: Checks to make sure the database has been connected to. If not, the
326: connection is established.
327:
328: =cut
329:
330: ###############################
331: sub connect_to_db {
332: return 1 if ($dbh);
333: if (! ($dbh = DBI->connect("DBI:mysql:loncapa","www",
334: $Apache::lonnet::perlvar{'lonSqlAccess'},
335: { RaiseError=>0,PrintError=>0}))) {
336: $debugstring = "Unable to connect to loncapa database.";
1.7 matthew 337: if (! defined($dbh)) {
338: $debugstring = "Unable to connect to loncapa database.";
339: $errorstring = "dbh was undefined.";
340: } elsif ($dbh->err) {
1.1 matthew 341: $errorstring = "Connection error: ".$dbh->errstr;
342: }
343: return undef;
344: }
345: $debugstring = "Successfully connected to loncapa database.";
1.13 matthew 346: return 1;
347: }
348:
349: ###############################
350:
351: =pod
352:
353: =item &verify_sql_connection()
354:
355: Inputs: none.
356:
357: Returns: 0 (failure) or 1 (success)
358:
359: Checks to make sure the database can be connected to. It does not
360: initialize anything in the lonmysql package.
361:
362: =cut
363:
364: ###############################
365: sub verify_sql_connection {
366: my $connection;
367: if (! ($connection = DBI->connect("DBI:mysql:loncapa","www",
368: $Apache::lonnet::perlvar{'lonSqlAccess'},
369: { RaiseError=>0,PrintError=>0}))) {
370: return 0;
371: }
372: undef($connection);
1.1 matthew 373: return 1;
374: }
375:
376: ###############################
377:
378: =pod
379:
380: =item &disconnect_from_db()
381:
382: Inputs: none.
383:
384: Returns: Always returns 1.
385:
386: Severs the connection to the mysql database.
387:
388: =cut
389:
390: ###############################
391: sub disconnect_from_db {
392: foreach (keys(%Tables)) {
393: # Supposedly, having statement handlers running around after the
394: # database connection has been lost will cause trouble. So we
395: # kill them off just to be sure.
396: if (exists($Tables{$_}->{'row_insert_sth'})) {
397: delete($Tables{$_}->{'row_insert_sth'});
398: }
1.9 matthew 399: if (exists($Tables{$_}->{'row_replace_sth'})) {
400: delete($Tables{$_}->{'row_replace_sth'});
401: }
1.1 matthew 402: }
403: $dbh->disconnect if ($dbh);
404: $debugstring = "Disconnected from database.";
405: $dbh = undef;
406: return 1;
407: }
408:
409: ###############################
410:
411: =pod
412:
1.2 matthew 413: =item &number_of_rows()
1.1 matthew 414:
1.2 matthew 415: Input: table identifier
416:
1.3 matthew 417: Returns: the number of rows in the given table, undef on error.
1.1 matthew 418:
419: =cut
420:
421: ###############################
1.2 matthew 422: sub number_of_rows {
423: my ($table_id) = @_;
1.3 matthew 424: return undef if (! defined(&connect_to_db()));
425: return undef if (! defined(&update_table_info($table_id)));
426: return $Tables{&translate_id($table_id)}->{'Rows'};
1.10 matthew 427: }
428: ###############################
429:
430: =pod
431:
432: =item &get_dbh()
433:
434: Input: nothing
435:
436: Returns: the database handler, or undef on error.
437:
438: This routine allows the programmer to gain access to the database handler.
439: Be careful.
440:
441: =cut
442:
443: ###############################
444: sub get_dbh {
445: return undef if (! defined(&connect_to_db()));
446: return $dbh;
1.1 matthew 447: }
448:
449: ###############################
450:
451: =pod
452:
453: =item &get_error()
454:
455: Inputs: none.
456:
457: Returns: The last error reported.
458:
459: =cut
460:
461: ###############################
462: sub get_error {
463: return $errorstring;
464: }
465:
466: ###############################
467:
468: =pod
469:
470: =item &get_debug()
471:
472: Inputs: none.
473:
474: Returns: A string describing the internal state of the lonmysql package.
475:
476: =cut
477:
478: ###############################
479: sub get_debug {
480: return $debugstring;
481: }
482:
483: ###############################
484:
485: =pod
486:
1.8 matthew 487: =item &update_table_info()
1.1 matthew 488:
489: Inputs: table id
490:
1.3 matthew 491: Returns: undef on error, 1 on success.
1.1 matthew 492:
1.3 matthew 493: &update_table_info updates the %Tables hash with current information about
494: the given table.
495:
496: The default MySQL table status fields are:
1.1 matthew 497:
498: Name Type Row_format
499: Max_data_length Index_length Data_free
500: Create_time Update_time Check_time
501: Avg_row_length Data_length Comment
502: Rows Auto_increment Create_options
503:
1.3 matthew 504: Additionally, "Col_order" is updated as well.
505:
1.1 matthew 506: =cut
507:
508: ###############################
1.3 matthew 509: sub update_table_info {
1.1 matthew 510: my ($table_id) = @_;
1.3 matthew 511: return undef if (! defined(&connect_to_db()));
512: my $table_status = &check_table($table_id);
513: return undef if (! defined($table_status));
514: if (! $table_status) {
515: $errorstring = "table $table_id does not exist.";
516: return undef;
517: }
1.1 matthew 518: my $tablename = &translate_id($table_id);
1.3 matthew 519: #
520: # Get MySQLs table status information.
521: #
1.1 matthew 522: my @tabledesc = qw/
523: Name Type Row_format Rows Avg_row_length Data_length
524: Max_data_length Index_length Data_free Auto_increment
525: Create_time Update_time Check_time Create_options Comment /;
526: my $db_command = "SHOW TABLE STATUS FROM loncapa LIKE '$tablename'";
527: my $sth = $dbh->prepare($db_command);
528: $sth->execute();
529: if ($sth->err) {
530: $errorstring = "$dbh ATTEMPTED:\n".$db_command."\nRESULTING ERROR:\n".
531: $sth->errstr;
1.3 matthew 532: &disconnect_from_db();
1.1 matthew 533: return undef;
534: }
535: #
536: my @info=$sth->fetchrow_array;
537: for (my $i=0;$i<= $#info ; $i++) {
1.3 matthew 538: $Tables{$tablename}->{$tabledesc[$i]}= $info[$i];
539: }
540: #
541: # Determine the column order
542: #
543: $db_command = "DESCRIBE $tablename";
1.5 matthew 544: $sth = $dbh->prepare($db_command);
1.3 matthew 545: $sth->execute();
546: if ($sth->err) {
547: $errorstring = "$dbh ATTEMPTED:\n".$db_command."\nRESULTING ERROR:\n".
548: $sth->errstr;
549: &disconnect_from_db();
550: return undef;
551: }
552: my $aref=$sth->fetchall_arrayref;
553: $Tables{$tablename}->{'Col_order'}=[]; # Clear values.
554: # The values we want are the 'Field' entries, the first column.
555: for (my $i=0;$i< @$aref ; $i++) {
556: push @{$Tables{$tablename}->{'Col_order'}},$aref->[$i]->[0];
1.1 matthew 557: }
558: #
559: $debugstring = "Retrieved table info for $tablename";
1.3 matthew 560: return 1;
1.1 matthew 561: }
1.18 ! www 562: ###############################
! 563:
! 564: =pod
! 565:
! 566: =item &col_order()
! 567:
! 568: Inputs: table id
1.1 matthew 569:
1.18 ! www 570: Returns: array with column order
! 571:
! 572: =cut
! 573:
! 574:
! 575: sub col_order {
! 576: my $table_id=shift;
! 577: if (&update_table_info($table_id)) {
! 578: return @{$Tables{$table_id}->{'Col_order'}};
! 579: } else {
! 580: return ();
! 581: }
! 582: }
1.1 matthew 583: ###############################
584:
585: =pod
586:
1.8 matthew 587: =item &create_table()
1.1 matthew 588:
589: Inputs:
590: table description
591:
592: Input formats:
593:
594: table description = {
595: permanent => 'yes' or 'no',
1.8 matthew 596: columns => [
597: { name => 'colA',
598: type => mysql type,
599: restrictions => 'NOT NULL' or empty,
600: primary_key => 'yes' or empty,
601: auto_inc => 'yes' or empty,
602: },
603: { name => 'colB',
604: ...
605: },
606: { name => 'colC',
607: ...
608: },
609: ],
1.9 matthew 610: 'PRIMARY KEY' => (index_col_name,...),
1.11 matthew 611: KEY => [{ name => 'idx_name',
612: columns => (col1,col2,..),},],
613: INDEX => [{ name => 'idx_name',
614: columns => (col1,col2,..),},],
615: UNIQUE => [{ index => 'yes',
1.9 matthew 616: name => 'idx_name',
1.11 matthew 617: columns => (col1,col2,..),},],
618: FULLTEXT => [{ index => 'yes',
1.9 matthew 619: name => 'idx_name',
1.11 matthew 620: columns => (col1,col2,..),},],
1.9 matthew 621:
1.1 matthew 622: }
623:
624: Returns:
625: undef on error, table id on success.
626:
627: =cut
628:
629: ###############################
630: sub create_table {
1.3 matthew 631: return undef if (!defined(&connect_to_db($dbh)));
1.1 matthew 632: my ($table_des)=@_;
633: #
634: # Build request to create table
635: ##################################
636: my @Columns;
637: my $col_des;
1.9 matthew 638: my $table_id;
639: if (exists($table_des->{'id'})) {
640: $table_id = $table_des->{'id'};
641: } else {
642: $table_id = &get_new_table_id();
643: }
1.3 matthew 644: my $tablename = &translate_id($table_id);
1.1 matthew 645: my $request = "CREATE TABLE IF NOT EXISTS ".$tablename." ";
1.8 matthew 646: foreach my $coldata (@{$table_des->{'columns'}}) {
647: my $column = $coldata->{'name'};
648: next if (! defined($column));
1.1 matthew 649: $col_des = '';
1.3 matthew 650: if (lc($coldata->{'type'}) =~ /(enum|set)/) { # 'enum' or 'set'
1.1 matthew 651: $col_des.=$column." ".$coldata->{'type'}."('".
652: join("', '",@{$coldata->{'values'}})."')";
653: } else {
654: $col_des.=$column." ".$coldata->{'type'};
655: if (exists($coldata->{'size'})) {
656: $col_des.="(".$coldata->{'size'}.")";
657: }
658: }
659: # Modifiers
660: if (exists($coldata->{'restrictions'})){
661: $col_des.=" ".$coldata->{'restrictions'};
662: }
663: if (exists($coldata->{'default'})) {
664: $col_des.=" DEFAULT '".$coldata->{'default'}."'";
665: }
1.3 matthew 666: $col_des.=' AUTO_INCREMENT' if (exists($coldata->{'auto_inc'}) &&
667: ($coldata->{'auto_inc'} eq 'yes'));
668: $col_des.=' PRIMARY KEY' if (exists($coldata->{'primary_key'}) &&
669: ($coldata->{'primary_key'} eq 'yes'));
1.1 matthew 670: } continue {
671: # skip blank items.
672: push (@Columns,$col_des) if ($col_des ne '');
673: }
1.9 matthew 674: if (exists($table_des->{'PRIMARY KEY'})) {
675: push (@Columns,'PRIMARY KEY ('.join(',',@{$table_des->{'PRIMARY KEY'}})
676: .')');
677: }
1.11 matthew 678: #
679: foreach my $indextype ('KEY','INDEX') {
680: next if (!exists($table_des->{$indextype}));
681: foreach my $indexdescription (@{$table_des->{$indextype}}) {
682: my $text = $indextype.' ';
683: if (exists($indexdescription->{'name'})) {
684: $text .=$indexdescription->{'name'};
1.9 matthew 685: }
1.11 matthew 686: $text .= ' ('.join(',',@{$indexdescription->{'columns'}}).')';
1.9 matthew 687: push (@Columns,$text);
688: }
689: }
1.11 matthew 690: #
691: foreach my $indextype ('UNIQUE','FULLTEXT') {
692: next if (! exists($table_des->{$indextype}));
693: foreach my $indexdescription (@{$table_des->{$indextype}}) {
694: my $text = $indextype.' ';
695: if (exists($indexdescription->{'index'}) &&
696: $indexdescription->{'index'} eq 'yes') {
1.9 matthew 697: $text .= 'INDEX ';
698: }
1.11 matthew 699: if (exists($indexdescription->{'name'})) {
700: $text .=$indexdescription->{'name'};
1.9 matthew 701: }
1.11 matthew 702: $text .= ' ('.join(',',@{$indexdescription->{'columns'}}).')';
1.9 matthew 703: push (@Columns,$text);
704: }
1.3 matthew 705: }
1.11 matthew 706: #
1.1 matthew 707: $request .= "(".join(", ",@Columns).") ";
708: unless($table_des->{'permanent'} eq 'yes') {
709: $request.="COMMENT = 'temporary' ";
710: }
711: $request .= "TYPE=MYISAM";
712: #
713: # Execute the request to create the table
714: #############################################
715: my $count = $dbh->do($request);
716: if (! defined($count)) {
1.3 matthew 717: $errorstring = "$dbh ATTEMPTED:\n".$request."\nRESULTING ERROR:\n";
1.1 matthew 718: return undef;
719: }
720: #
721: # Set up the internal bookkeeping
722: #############################################
723: delete($Tables{$tablename}) if (exists($Tables{$tablename}));
1.3 matthew 724: return undef if (! defined(&update_table_info($table_id)));
725: $debugstring = "Created table $tablename at time ".time.
1.1 matthew 726: " with request\n$request";
1.3 matthew 727: return $table_id;
1.1 matthew 728: }
729:
730: ###############################
731:
732: =pod
733:
1.8 matthew 734: =item &get_new_table_id()
1.1 matthew 735:
736: Used internally to prevent table name collisions.
737:
738: =cut
739:
740: ###############################
741: sub get_new_table_id {
742: my $newid = 0;
743: my @tables = &tables_in_db();
744: foreach (@tables) {
745: if (/^$ENV{'user.name'}_$ENV{'user.domain'}_(\d+)$/) {
746: $newid = $1 if ($1 > $newid);
747: }
748: }
749: return ++$newid;
750: }
751:
752: ###############################
753:
754: =pod
755:
1.8 matthew 756: =item &get_rows()
1.1 matthew 757:
758: Inputs: $table_id,$condition
759:
760: Returns: undef on error, an array ref to (array of) results on success.
761:
1.2 matthew 762: Internally, this function does a 'SELECT * FROM table WHERE $condition'.
1.1 matthew 763: $condition = 'id>0' will result in all rows where column 'id' has a value
764: greater than 0 being returned.
765:
766: =cut
767:
768: ###############################
769: sub get_rows {
770: my ($table_id,$condition) = @_;
1.3 matthew 771: return undef if (! defined(&connect_to_db()));
772: my $table_status = &check_table($table_id);
773: return undef if (! defined($table_status));
774: if (! $table_status) {
775: $errorstring = "table $table_id does not exist.";
776: return undef;
777: }
1.1 matthew 778: my $tablename = &translate_id($table_id);
1.9 matthew 779: my $request;
780: if (defined($condition) && $condition ne '') {
781: $request = 'SELECT * FROM '.$tablename.' WHERE '.$condition;
782: } else {
783: $request = 'SELECT * FROM '.$tablename;
784: $condition = 'no condition';
785: }
1.1 matthew 786: my $sth=$dbh->prepare($request);
787: $sth->execute();
788: if ($sth->err) {
789: $errorstring = "$dbh ATTEMPTED:\n".$request."\nRESULTING ERROR:\n".
790: $sth->errstr;
791: $debugstring = "Failed to get rows matching $condition";
792: return undef;
793: }
794: $debugstring = "Got rows matching $condition";
795: my @Results = @{$sth->fetchall_arrayref};
796: return @Results;
797: }
798:
799: ###############################
800:
801: =pod
802:
1.8 matthew 803: =item &store_row()
1.1 matthew 804:
805: Inputs: table id, row data
806:
807: returns undef on error, 1 on success.
808:
809: =cut
810:
811: ###############################
812: sub store_row {
813: my ($table_id,$rowdata) = @_;
1.3 matthew 814: #
815: return undef if (! defined(&connect_to_db()));
816: my $table_status = &check_table($table_id);
817: return undef if (! defined($table_status));
818: if (! $table_status) {
819: $errorstring = "table $table_id does not exist.";
820: return undef;
821: }
822: #
1.1 matthew 823: my $tablename = &translate_id($table_id);
1.3 matthew 824: #
1.1 matthew 825: my $sth;
1.3 matthew 826: if (exists($Tables{$tablename}->{'row_insert_sth'})) {
827: $sth = $Tables{$tablename}->{'row_insert_sth'};
1.1 matthew 828: } else {
1.3 matthew 829: # Build the insert statement handler
830: return undef if (! defined(&update_table_info($table_id)));
1.1 matthew 831: my $insert_request = 'INSERT INTO '.$tablename.' VALUES(';
1.3 matthew 832: foreach (@{$Tables{$tablename}->{'Col_order'}}) {
1.1 matthew 833: $insert_request.="?,";
834: }
835: chop $insert_request;
836: $insert_request.=")";
837: $sth=$dbh->prepare($insert_request);
1.3 matthew 838: $Tables{$tablename}->{'row_insert_sth'}=$sth;
1.1 matthew 839: }
840: my @Parameters;
841: if (ref($rowdata) eq 'ARRAY') {
842: @Parameters = @$rowdata;
843: } elsif (ref($rowdata) eq 'HASH') {
1.3 matthew 844: foreach (@{$Tables{$tablename}->{'Col_order'}}) {
1.6 matthew 845: push(@Parameters,$rowdata->{$_});
1.1 matthew 846: }
847: }
848: $sth->execute(@Parameters);
849: if ($sth->err) {
850: $errorstring = "$dbh ATTEMPTED insert @Parameters RESULTING ERROR:\n".
851: $sth->errstr;
852: return undef;
853: }
854: $debugstring = "Stored row.";
855: return 1;
856: }
857:
1.9 matthew 858: ###############################
859:
860: =pod
861:
862: =item &replace_row()
863:
864: Inputs: table id, row data
865:
866: returns undef on error, 1 on success.
867:
868: Acts like &store_row() but uses the 'REPLACE' command instead of 'INSERT'.
869:
870: =cut
871:
872: ###############################
873: sub replace_row {
874: my ($table_id,$rowdata) = @_;
875: #
876: return undef if (! defined(&connect_to_db()));
877: my $table_status = &check_table($table_id);
878: return undef if (! defined($table_status));
879: if (! $table_status) {
880: $errorstring = "table $table_id does not exist.";
881: return undef;
882: }
883: #
884: my $tablename = &translate_id($table_id);
885: #
886: my $sth;
887: if (exists($Tables{$tablename}->{'row_replace_sth'})) {
888: $sth = $Tables{$tablename}->{'row_replace_sth'};
889: } else {
890: # Build the insert statement handler
891: return undef if (! defined(&update_table_info($table_id)));
892: my $replace_request = 'REPLACE INTO '.$tablename.' VALUES(';
893: foreach (@{$Tables{$tablename}->{'Col_order'}}) {
894: $replace_request.="?,";
895: }
896: chop $replace_request;
897: $replace_request.=")";
898: $sth=$dbh->prepare($replace_request);
899: $Tables{$tablename}->{'row_replace_sth'}=$sth;
900: }
901: my @Parameters;
902: if (ref($rowdata) eq 'ARRAY') {
903: @Parameters = @$rowdata;
904: } elsif (ref($rowdata) eq 'HASH') {
905: foreach (@{$Tables{$tablename}->{'Col_order'}}) {
906: push(@Parameters,$rowdata->{$_});
907: }
908: }
909: $sth->execute(@Parameters);
910: if ($sth->err) {
911: $errorstring = "$dbh ATTEMPTED replace @Parameters RESULTING ERROR:\n".
912: $sth->errstr;
913: return undef;
914: }
915: $debugstring = "Stored row.";
916: return 1;
917: }
918:
1.1 matthew 919: ###########################################
920:
921: =pod
922:
1.8 matthew 923: =item &tables_in_db()
1.1 matthew 924:
925: Returns a list containing the names of all the tables in the database.
926: Returns undef on error.
927:
928: =cut
929:
930: ###########################################
931: sub tables_in_db {
1.3 matthew 932: return undef if (!defined(&connect_to_db()));
1.5 matthew 933: my $sth=$dbh->prepare('SHOW TABLES');
1.1 matthew 934: $sth->execute();
935: if ($sth->err) {
1.3 matthew 936: $errorstring = "$dbh ATTEMPTED:\n".'SHOW TABLES'.
937: "\nRESULTING ERROR:\n".$sth->errstr;
1.1 matthew 938: return undef;
939: }
940: my $aref = $sth->fetchall_arrayref;
941: my @table_list=();
942: foreach (@$aref) {
943: push @table_list,$_->[0];
944: }
945: $debugstring = "Got list of tables in DB: @table_list";
946: return @table_list;
947: }
948:
949: ###########################################
950:
951: =pod
952:
1.8 matthew 953: =item &translate_id()
1.1 matthew 954:
955: Used internally to translate a numeric table id into a MySQL table name.
956: If the input $id contains non-numeric characters it is assumed to have
957: already been translated.
958:
959: Checks are NOT performed to see if the table actually exists.
960:
961: =cut
962:
963: ###########################################
964: sub translate_id {
965: my $id = shift;
966: # id should be a digit. If it is not a digit we assume the given id
967: # is complete and does not need to be translated.
968: return $id if ($id =~ /\D/);
969: return $ENV{'user.name'}.'_'.$ENV{'user.domain'}.'_'.$id;
970: }
971:
972: ###########################################
973:
974: =pod
975:
1.8 matthew 976: =item &check_table()
977:
978: Input: table id
1.1 matthew 979:
980: Checks to see if the requested table exists. Returns 0 (no), 1 (yes), or
981: undef (error).
982:
983: =cut
984:
985: ###########################################
986: sub check_table {
987: my $table_id = shift;
1.3 matthew 988: return undef if (!defined(&connect_to_db()));
989: #
1.1 matthew 990: $table_id = &translate_id($table_id);
991: my @Table_list = &tables_in_db();
992: my $result = 0;
993: foreach (@Table_list) {
1.9 matthew 994: if ($_ eq $table_id) {
1.1 matthew 995: $result = 1;
996: last;
997: }
998: }
999: # If it does not exist, make sure we do not have it listed in %Tables
1000: delete($Tables{$table_id}) if ((! $result) && exists($Tables{$table_id}));
1001: $debugstring = "check_table returned $result for $table_id";
1002: return $result;
1003: }
1004:
1.5 matthew 1005: ###########################################
1006:
1007: =pod
1008:
1.8 matthew 1009: =item &remove_from_table()
1010:
1011: Input: $table_id, $column, $value
1012:
1013: Returns: the number of rows deleted. undef on error.
1.5 matthew 1014:
1015: Executes a "delete from $tableid where $column like binary '$value'".
1016:
1017: =cut
1018:
1019: ###########################################
1020: sub remove_from_table {
1021: my ($table_id,$column,$value) = @_;
1022: return undef if (!defined(&connect_to_db()));
1023: #
1024: $table_id = &translate_id($table_id);
1.17 www 1025: my $command = 'DELETE FROM '.$table_id.' WHERE '.$column.
1.5 matthew 1026: " LIKE BINARY ".$dbh->quote($value);
1027: my $sth = $dbh->prepare($command);
1.17 www 1028: unless ($sth->execute()) {
1.5 matthew 1029: $errorstring = "ERROR on execution of ".$command."\n".$sth->errstr;
1030: return undef;
1031: }
1.12 matthew 1032: $debugstring = $command;
1.5 matthew 1033: my $rows = $sth->rows;
1034: return $rows;
1035: }
1036:
1.14 matthew 1037: ###########################################
1038:
1039: =pod
1040:
1041: =item drop_table($table_id)
1042:
1043: Issues a 'drop table if exists' command
1044:
1045: =cut
1046:
1047: ###########################################
1048:
1049: sub drop_table {
1050: my ($table_id) = @_;
1051: return undef if (!defined(&connect_to_db()));
1052: #
1053: $table_id = &translate_id($table_id);
1054: my $command = 'DROP TABLE IF EXISTS '.$table_id;
1055: my $sth = $dbh->prepare($command);
1056: $sth->execute();
1057: if ($sth->err) {
1058: $errorstring = "ERROR on execution of ".$command."\n".$sth->errstr;
1059: return undef;
1060: }
1061: $debugstring = $command;
1.15 matthew 1062: delete($Tables{$table_id}); # remove any knowledge of the table
1.14 matthew 1063: return 1; # if we got here there was no error, so return a 'true' value
1064: }
1.16 www 1065:
1066:
1067:
1068:
1069: # ---------------------------- convert 'time' format into a datetime sql format
1070: sub sqltime {
1071: my ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst) =
1072: localtime(&unsqltime($_[0]));
1073: $mon++; $year+=1900;
1074: return "$year-$mon-$mday $hour:$min:$sec";
1075: }
1076:
1077: sub maketime {
1078: my %th=@_;
1079: return POSIX::mktime(($th{'seconds'},$th{'minutes'},$th{'hours'},
1080: $th{'day'},$th{'month'}-1,
1081: $th{'year'}-1900,0,0,$th{'dlsav'}));
1082: }
1083:
1084:
1085: #########################################
1086: #
1087: # Retro-fixing of un-backward-compatible time format
1088:
1089: sub unsqltime {
1090: my $timestamp=shift;
1091: if ($timestamp=~/^(\d+)\-(\d+)\-(\d+)\s+(\d+)\:(\d+)\:(\d+)$/) {
1092: $timestamp=&maketime('year'=>$1,'month'=>$2,'day'=>$3,
1093: 'hours'=>$4,'minutes'=>$5,'seconds'=>$6);
1094: }
1095: return $timestamp;
1096: }
1097:
1.5 matthew 1098:
1.1 matthew 1099: 1;
1100:
1101: __END__;
1.5 matthew 1102:
1103: =pod
1104:
1105: =back
1106:
1107: =cut
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