Annotation of loncom/interface/lonmysql.pm, revision 1.9
1.1 matthew 1: # The LearningOnline Network with CAPA
2: # MySQL utility functions
3: #
1.9 ! matthew 4: # $Id: lonmysql.pm,v 1.8 2003/03/10 21:22:36 matthew 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();
35:
36: ######################################################################
37: ######################################################################
38:
39: =pod
40:
41: =head1 Name
42:
43: lonmysql - LONCAPA MySQL utility functions
44:
45: =head1 Synopsis
46:
47: lonmysql contains utility functions to make accessing the mysql loncapa
48: database easier.
49:
50: =head1 Description
51:
52: lonmysql does its best to encapsulate all the database/table functions
53: and provide a common interface. The goal, however, is not to provide
54: a complete reimplementation of the DBI interface. Instead we try to
55: make using mysql as painless as possible.
56:
57: Each table has a numeric ID that is a parameter to most lonmysql functions.
58: The table id is returned by &create_table.
59: If you lose the table id, it is lost forever.
60: The table names in MySQL correspond to
61: $ENV{'user.name'}.'_'.$ENV{'user.domain'}.'_'.$table_id. If the table id
62: is non-numeric, it is assumed to be the full name of a table. If you pass
63: the table id in a form, you MUST ensure that what you send to lonmysql is
64: numeric, otherwise you are opening up all the tables in the MySQL database.
65:
66: =over 4
67:
68: =item Creating a table
69:
70: To create a table, you need a description of its structure. See the entry
71: for &create_table for a description of what is needed.
72:
73: $table_id = &create_table({
1.9 ! matthew 74: id => 'tableid', # usually you will use the returned id
! 75: columns => (
! 76: { name => 'id',
! 77: type => 'INT',
! 78: restrictions => 'NOT NULL',
! 79: primary_key => 'yes',
! 80: auto_inc => 'yes'
! 81: },
! 82: { name => 'verbage',
! 83: type => 'TEXT' },
! 84: ),
! 85: fulltext => [qw/verbage/],
1.3 matthew 86: });
1.1 matthew 87:
88: The above command will create a table with two columns, 'id' and 'verbage'.
89:
90: 'id' will be an integer which is autoincremented and non-null.
91:
92: 'verbage' will be of type 'TEXT', which (conceivably) allows any length
93: text string to be stored. Depending on your intentions for this database,
94: setting restrictions => 'NOT NULL' may help you avoid storing empty data.
95:
1.3 matthew 96: the fulltext element sets up the 'verbage' column for 'FULLTEXT' searching.
1.1 matthew 97:
98:
99:
100: =item Storing rows
101:
102: Storing a row in a table requires calling &store_row($table_id,$data)
103:
104: $data is either a hash reference or an array reference. If it is an array
105: reference, the data is passed as is (after being escaped) to the
106: "INSERT INTO <table> VALUES( ... )" SQL command. If $data is a hash reference,
107: the data will be placed into an array in the proper column order for the table
108: and then passed to the database.
109:
110: An example of inserting into the table created above is:
111:
112: &store_row($table_id,[undef,'I am not a crackpot!']);
113:
114: or equivalently,
115:
116: &store_row($table_id,{ verbage => 'I am not a crackpot!'});
117:
118: Since the above table was created with the first column ('id') as
119: autoincrement, providing a value is unnecessary even though the column was
120: marked as 'NOT NULL'.
121:
122:
123:
124: =item Retrieving rows
125:
126: Retrieving rows requires calling get_rows:
127:
128: @row = &Apache::lonmysql::get_rows($table_id,$condition)
129:
130: This results in the query "SELECT * FROM <table> HAVING $condition".
131:
132: @row = &Apache::lonmysql::get_rows($table_id,'id>20');
133:
134: returns all rows with column 'id' greater than 20.
135:
136: =back
137:
138: =cut
139:
140: ######################################################################
141: ######################################################################
142: =pod
143:
144: =head1 Package Variables
145:
146: =over 4
147:
148: =cut
149:
150: ##################################################
151: ##################################################
152:
153: =pod
154:
155: =item %Tables
156:
157: Holds information regarding the currently open connections. Each key
158: in the %Tables hash will be a unique table key. The value associated
159: with a key is a hash reference. Most values are initialized when the
160: table is created.
161:
162: The following entries are allowed in the hash reference:
163:
164: =over 4
165:
1.3 matthew 166: =item Name
167:
168: Table name.
169:
170: =item Type
171:
172: The type of table, typically MyISAM.
173:
174: =item Row_format
175:
176: Describes how rows should be stored in the table. DYNAMIC or STATIC.
177:
178: =item Create_time
179:
180: The date of the tables creation.
181:
182: =item Update_time
183:
184: The date of the last modification of the table.
185:
186: =item Check_time
187:
188: Usually NULL.
189:
190: =item Avg_row_length
191:
192: The average length of the rows.
193:
194: =item Data_length
195:
196: The length of the data stored in the table (bytes)
197:
198: =item Max_data_length
199:
200: The maximum possible size of the table (bytes).
1.1 matthew 201:
1.3 matthew 202: =item Index_length
1.1 matthew 203:
1.3 matthew 204: The length of the index for the table (bytes)
1.1 matthew 205:
1.3 matthew 206: =item Data_free
1.1 matthew 207:
1.3 matthew 208: I have no idea what this is.
1.1 matthew 209:
1.3 matthew 210: =item Comment
1.1 matthew 211:
1.3 matthew 212: The comment associated with the table.
213:
214: =item Rows
215:
216: The number of rows in the table.
217:
218: =item Auto_increment
219:
220: The value of the next auto_increment field.
221:
222: =item Create_options
223:
224: I have no idea.
225:
226: =item Col_order
227:
228: an array reference which holds the order of columns in the table.
229:
230: =item row_insert_sth
1.1 matthew 231:
232: The statement handler for row inserts.
233:
1.9 ! matthew 234: =item row_replace_sth
! 235:
! 236: The statement handler for row inserts.
! 237:
1.1 matthew 238: =back
239:
1.3 matthew 240: Col_order and row_insert_sth are kept internally by lonmysql and are not
241: part of the usual MySQL table information.
242:
1.1 matthew 243: =cut
244:
245: ##################################################
246: ##################################################
247: my %Tables;
248:
249: ##################################################
250: ##################################################
251: =pod
252:
253: =item $errorstring
254:
255: Holds the last error.
256:
257: =cut
258: ##################################################
259: ##################################################
260: my $errorstring;
261:
262: ##################################################
263: ##################################################
264: =pod
265:
266: =item $debugstring
267:
268: Describes current events within the package.
269:
270: =cut
271: ##################################################
272: ##################################################
273: my $debugstring;
274:
275: ##################################################
276: ##################################################
277:
278: =pod
279:
280: =item $dbh
281:
282: The database handler; The actual connection to MySQL via the perl DBI.
283:
284: =cut
285:
286: ##################################################
287: ##################################################
288: my $dbh;
289:
290: ##################################################
291: ##################################################
292:
293: # End of global variable declarations
294:
295: =pod
296:
297: =back
298:
299: =cut
300:
301: ######################################################################
302: ######################################################################
303:
304: =pod
305:
306: =head1 Internals
307:
308: =over 4
309:
310: =cut
311:
312: ######################################################################
313: ######################################################################
314:
315: =pod
316:
317: =item &connect_to_db()
318:
319: Inputs: none.
320:
321: Returns: undef on error, 1 on success.
322:
323: Checks to make sure the database has been connected to. If not, the
324: connection is established.
325:
326: =cut
327:
328: ###############################
329: sub connect_to_db {
330: return 1 if ($dbh);
331: if (! ($dbh = DBI->connect("DBI:mysql:loncapa","www",
332: $Apache::lonnet::perlvar{'lonSqlAccess'},
333: { RaiseError=>0,PrintError=>0}))) {
334: $debugstring = "Unable to connect to loncapa database.";
1.7 matthew 335: if (! defined($dbh)) {
336: $debugstring = "Unable to connect to loncapa database.";
337: $errorstring = "dbh was undefined.";
338: } elsif ($dbh->err) {
1.1 matthew 339: $errorstring = "Connection error: ".$dbh->errstr;
340: }
341: return undef;
342: }
343: $debugstring = "Successfully connected to loncapa database.";
344: return 1;
345: }
346:
347: ###############################
348:
349: =pod
350:
351: =item &disconnect_from_db()
352:
353: Inputs: none.
354:
355: Returns: Always returns 1.
356:
357: Severs the connection to the mysql database.
358:
359: =cut
360:
361: ###############################
362: sub disconnect_from_db {
363: foreach (keys(%Tables)) {
364: # Supposedly, having statement handlers running around after the
365: # database connection has been lost will cause trouble. So we
366: # kill them off just to be sure.
367: if (exists($Tables{$_}->{'row_insert_sth'})) {
368: delete($Tables{$_}->{'row_insert_sth'});
369: }
1.9 ! matthew 370: if (exists($Tables{$_}->{'row_replace_sth'})) {
! 371: delete($Tables{$_}->{'row_replace_sth'});
! 372: }
1.1 matthew 373: }
374: $dbh->disconnect if ($dbh);
375: $debugstring = "Disconnected from database.";
376: $dbh = undef;
377: return 1;
378: }
379:
380: ###############################
381:
382: =pod
383:
1.2 matthew 384: =item &number_of_rows()
1.1 matthew 385:
1.2 matthew 386: Input: table identifier
387:
1.3 matthew 388: Returns: the number of rows in the given table, undef on error.
1.1 matthew 389:
390: =cut
391:
392: ###############################
1.2 matthew 393: sub number_of_rows {
394: my ($table_id) = @_;
1.3 matthew 395: return undef if (! defined(&connect_to_db()));
396: return undef if (! defined(&update_table_info($table_id)));
397: return $Tables{&translate_id($table_id)}->{'Rows'};
1.1 matthew 398: }
399:
400: ###############################
401:
402: =pod
403:
404: =item &get_error()
405:
406: Inputs: none.
407:
408: Returns: The last error reported.
409:
410: =cut
411:
412: ###############################
413: sub get_error {
414: return $errorstring;
415: }
416:
417: ###############################
418:
419: =pod
420:
421: =item &get_debug()
422:
423: Inputs: none.
424:
425: Returns: A string describing the internal state of the lonmysql package.
426:
427: =cut
428:
429: ###############################
430: sub get_debug {
431: return $debugstring;
432: }
433:
434: ###############################
435:
436: =pod
437:
1.8 matthew 438: =item &update_table_info()
1.1 matthew 439:
440: Inputs: table id
441:
1.3 matthew 442: Returns: undef on error, 1 on success.
1.1 matthew 443:
1.3 matthew 444: &update_table_info updates the %Tables hash with current information about
445: the given table.
446:
447: The default MySQL table status fields are:
1.1 matthew 448:
449: Name Type Row_format
450: Max_data_length Index_length Data_free
451: Create_time Update_time Check_time
452: Avg_row_length Data_length Comment
453: Rows Auto_increment Create_options
454:
1.3 matthew 455: Additionally, "Col_order" is updated as well.
456:
1.1 matthew 457: =cut
458:
459: ###############################
1.3 matthew 460: sub update_table_info {
1.1 matthew 461: my ($table_id) = @_;
1.3 matthew 462: return undef if (! defined(&connect_to_db()));
463: my $table_status = &check_table($table_id);
464: return undef if (! defined($table_status));
465: if (! $table_status) {
466: $errorstring = "table $table_id does not exist.";
467: return undef;
468: }
1.1 matthew 469: my $tablename = &translate_id($table_id);
1.3 matthew 470: #
471: # Get MySQLs table status information.
472: #
1.1 matthew 473: my @tabledesc = qw/
474: Name Type Row_format Rows Avg_row_length Data_length
475: Max_data_length Index_length Data_free Auto_increment
476: Create_time Update_time Check_time Create_options Comment /;
477: my $db_command = "SHOW TABLE STATUS FROM loncapa LIKE '$tablename'";
478: my $sth = $dbh->prepare($db_command);
479: $sth->execute();
480: if ($sth->err) {
481: $errorstring = "$dbh ATTEMPTED:\n".$db_command."\nRESULTING ERROR:\n".
482: $sth->errstr;
1.3 matthew 483: &disconnect_from_db();
1.1 matthew 484: return undef;
485: }
486: #
487: my @info=$sth->fetchrow_array;
488: for (my $i=0;$i<= $#info ; $i++) {
1.3 matthew 489: $Tables{$tablename}->{$tabledesc[$i]}= $info[$i];
490: }
491: #
492: # Determine the column order
493: #
494: $db_command = "DESCRIBE $tablename";
1.5 matthew 495: $sth = $dbh->prepare($db_command);
1.3 matthew 496: $sth->execute();
497: if ($sth->err) {
498: $errorstring = "$dbh ATTEMPTED:\n".$db_command."\nRESULTING ERROR:\n".
499: $sth->errstr;
500: &disconnect_from_db();
501: return undef;
502: }
503: my $aref=$sth->fetchall_arrayref;
504: $Tables{$tablename}->{'Col_order'}=[]; # Clear values.
505: # The values we want are the 'Field' entries, the first column.
506: for (my $i=0;$i< @$aref ; $i++) {
507: push @{$Tables{$tablename}->{'Col_order'}},$aref->[$i]->[0];
1.1 matthew 508: }
509: #
510: $debugstring = "Retrieved table info for $tablename";
1.3 matthew 511: return 1;
1.1 matthew 512: }
513:
514: ###############################
515:
516: =pod
517:
1.8 matthew 518: =item &create_table()
1.1 matthew 519:
520: Inputs:
521: table description
522:
523: Input formats:
524:
525: table description = {
526: permanent => 'yes' or 'no',
1.8 matthew 527: columns => [
528: { name => 'colA',
529: type => mysql type,
530: restrictions => 'NOT NULL' or empty,
531: primary_key => 'yes' or empty,
532: auto_inc => 'yes' or empty,
533: },
534: { name => 'colB',
535: ...
536: },
537: { name => 'colC',
538: ...
539: },
540: ],
1.9 ! matthew 541: 'PRIMARY KEY' => (index_col_name,...),
! 542: KEY => { name => 'idx_name',
! 543: columns => (col1,col2,..),},
! 544: INDEX => { name => 'idx_name',
! 545: columns => (col1,col2,..),},
! 546: UNIQUE => { index => 'yes',
! 547: name => 'idx_name',
! 548: columns => (col1,col2,..),},
! 549: FULLTEXT => { index => 'yes',
! 550: name => 'idx_name',
! 551: columns => (col1,col2,..),},
! 552:
1.1 matthew 553: }
554:
555: Returns:
556: undef on error, table id on success.
557:
558: =cut
559:
560: ###############################
561: sub create_table {
1.3 matthew 562: return undef if (!defined(&connect_to_db($dbh)));
1.1 matthew 563: my ($table_des)=@_;
564: #
565: # Build request to create table
566: ##################################
567: my @Columns;
568: my $col_des;
1.9 ! matthew 569: my $table_id;
! 570: if (exists($table_des->{'id'})) {
! 571: $table_id = $table_des->{'id'};
! 572: } else {
! 573: $table_id = &get_new_table_id();
! 574: }
1.3 matthew 575: my $tablename = &translate_id($table_id);
1.1 matthew 576: my $request = "CREATE TABLE IF NOT EXISTS ".$tablename." ";
1.8 matthew 577: foreach my $coldata (@{$table_des->{'columns'}}) {
578: my $column = $coldata->{'name'};
579: next if (! defined($column));
1.1 matthew 580: $col_des = '';
1.3 matthew 581: if (lc($coldata->{'type'}) =~ /(enum|set)/) { # 'enum' or 'set'
1.1 matthew 582: $col_des.=$column." ".$coldata->{'type'}."('".
583: join("', '",@{$coldata->{'values'}})."')";
584: } else {
585: $col_des.=$column." ".$coldata->{'type'};
586: if (exists($coldata->{'size'})) {
587: $col_des.="(".$coldata->{'size'}.")";
588: }
589: }
590: # Modifiers
591: if (exists($coldata->{'restrictions'})){
592: $col_des.=" ".$coldata->{'restrictions'};
593: }
594: if (exists($coldata->{'default'})) {
595: $col_des.=" DEFAULT '".$coldata->{'default'}."'";
596: }
1.3 matthew 597: $col_des.=' AUTO_INCREMENT' if (exists($coldata->{'auto_inc'}) &&
598: ($coldata->{'auto_inc'} eq 'yes'));
599: $col_des.=' PRIMARY KEY' if (exists($coldata->{'primary_key'}) &&
600: ($coldata->{'primary_key'} eq 'yes'));
1.1 matthew 601: } continue {
602: # skip blank items.
603: push (@Columns,$col_des) if ($col_des ne '');
604: }
1.9 ! matthew 605: if (exists($table_des->{'PRIMARY KEY'})) {
! 606: push (@Columns,'PRIMARY KEY ('.join(',',@{$table_des->{'PRIMARY KEY'}})
! 607: .')');
! 608: }
! 609: foreach ('KEY','INDEX') {
! 610: if (exists($table_des->{$_})) {
! 611: my $text = $_.' ';
! 612: if (exists($table_des->{$_}->{'name'})) {
! 613: $text .=$table_des->{$_}->{'name'};
! 614: }
! 615: $text .= ' ('.join(',',@{$table_des->{$_}->{'columns'}}).')';
! 616: push (@Columns,$text);
! 617: }
! 618: }
! 619: foreach ('UNIQUE','FULLTEXT') {
! 620: if (exists($table_des->{$_})) {
! 621: my $text = $_.' ';
! 622: if (exists($table_des->{$_}->{'index'}) &&
! 623: $table_des->{$_}->{'index'} eq 'yes') {
! 624: $text .= 'INDEX ';
! 625: }
! 626: if (exists($table_des->{$_}->{'name'})) {
! 627: $text .=$table_des->{$_}->{'name'};
! 628: }
! 629: $text .= ' ('.join(',',@{$table_des->{$_}->{'columns'}}).')';
! 630: push (@Columns,$text);
! 631: }
1.3 matthew 632: }
1.1 matthew 633: $request .= "(".join(", ",@Columns).") ";
634: unless($table_des->{'permanent'} eq 'yes') {
635: $request.="COMMENT = 'temporary' ";
636: }
637: $request .= "TYPE=MYISAM";
638: #
639: # Execute the request to create the table
640: #############################################
641: my $count = $dbh->do($request);
642: if (! defined($count)) {
1.3 matthew 643: $errorstring = "$dbh ATTEMPTED:\n".$request."\nRESULTING ERROR:\n";
1.1 matthew 644: return undef;
645: }
646: #
647: # Set up the internal bookkeeping
648: #############################################
649: delete($Tables{$tablename}) if (exists($Tables{$tablename}));
1.3 matthew 650: return undef if (! defined(&update_table_info($table_id)));
651: $debugstring = "Created table $tablename at time ".time.
1.1 matthew 652: " with request\n$request";
1.3 matthew 653: return $table_id;
1.1 matthew 654: }
655:
656: ###############################
657:
658: =pod
659:
1.8 matthew 660: =item &get_new_table_id()
1.1 matthew 661:
662: Used internally to prevent table name collisions.
663:
664: =cut
665:
666: ###############################
667: sub get_new_table_id {
668: my $newid = 0;
669: my @tables = &tables_in_db();
670: foreach (@tables) {
671: if (/^$ENV{'user.name'}_$ENV{'user.domain'}_(\d+)$/) {
672: $newid = $1 if ($1 > $newid);
673: }
674: }
675: return ++$newid;
676: }
677:
678: ###############################
679:
680: =pod
681:
1.8 matthew 682: =item &get_rows()
1.1 matthew 683:
684: Inputs: $table_id,$condition
685:
686: Returns: undef on error, an array ref to (array of) results on success.
687:
1.2 matthew 688: Internally, this function does a 'SELECT * FROM table WHERE $condition'.
1.1 matthew 689: $condition = 'id>0' will result in all rows where column 'id' has a value
690: greater than 0 being returned.
691:
692: =cut
693:
694: ###############################
695: sub get_rows {
696: my ($table_id,$condition) = @_;
1.3 matthew 697: return undef if (! defined(&connect_to_db()));
698: my $table_status = &check_table($table_id);
699: return undef if (! defined($table_status));
700: if (! $table_status) {
701: $errorstring = "table $table_id does not exist.";
702: return undef;
703: }
1.1 matthew 704: my $tablename = &translate_id($table_id);
1.9 ! matthew 705: my $request;
! 706: if (defined($condition) && $condition ne '') {
! 707: $request = 'SELECT * FROM '.$tablename.' WHERE '.$condition;
! 708: } else {
! 709: $request = 'SELECT * FROM '.$tablename;
! 710: $condition = 'no condition';
! 711: }
1.1 matthew 712: my $sth=$dbh->prepare($request);
713: $sth->execute();
714: if ($sth->err) {
715: $errorstring = "$dbh ATTEMPTED:\n".$request."\nRESULTING ERROR:\n".
716: $sth->errstr;
717: $debugstring = "Failed to get rows matching $condition";
718: return undef;
719: }
720: $debugstring = "Got rows matching $condition";
721: my @Results = @{$sth->fetchall_arrayref};
722: return @Results;
723: }
724:
725: ###############################
726:
727: =pod
728:
1.8 matthew 729: =item &store_row()
1.1 matthew 730:
731: Inputs: table id, row data
732:
733: returns undef on error, 1 on success.
734:
735: =cut
736:
737: ###############################
738: sub store_row {
739: my ($table_id,$rowdata) = @_;
1.3 matthew 740: #
741: return undef if (! defined(&connect_to_db()));
742: my $table_status = &check_table($table_id);
743: return undef if (! defined($table_status));
744: if (! $table_status) {
745: $errorstring = "table $table_id does not exist.";
746: return undef;
747: }
748: #
1.1 matthew 749: my $tablename = &translate_id($table_id);
1.3 matthew 750: #
1.1 matthew 751: my $sth;
1.3 matthew 752: if (exists($Tables{$tablename}->{'row_insert_sth'})) {
753: $sth = $Tables{$tablename}->{'row_insert_sth'};
1.1 matthew 754: } else {
1.3 matthew 755: # Build the insert statement handler
756: return undef if (! defined(&update_table_info($table_id)));
1.1 matthew 757: my $insert_request = 'INSERT INTO '.$tablename.' VALUES(';
1.3 matthew 758: foreach (@{$Tables{$tablename}->{'Col_order'}}) {
1.1 matthew 759: $insert_request.="?,";
760: }
761: chop $insert_request;
762: $insert_request.=")";
763: $sth=$dbh->prepare($insert_request);
1.3 matthew 764: $Tables{$tablename}->{'row_insert_sth'}=$sth;
1.1 matthew 765: }
766: my @Parameters;
767: if (ref($rowdata) eq 'ARRAY') {
768: @Parameters = @$rowdata;
769: } elsif (ref($rowdata) eq 'HASH') {
1.3 matthew 770: foreach (@{$Tables{$tablename}->{'Col_order'}}) {
1.6 matthew 771: push(@Parameters,$rowdata->{$_});
1.1 matthew 772: }
773: }
774: $sth->execute(@Parameters);
775: if ($sth->err) {
776: $errorstring = "$dbh ATTEMPTED insert @Parameters RESULTING ERROR:\n".
777: $sth->errstr;
778: return undef;
779: }
780: $debugstring = "Stored row.";
781: return 1;
782: }
783:
1.9 ! matthew 784: ###############################
! 785:
! 786: =pod
! 787:
! 788: =item &replace_row()
! 789:
! 790: Inputs: table id, row data
! 791:
! 792: returns undef on error, 1 on success.
! 793:
! 794: Acts like &store_row() but uses the 'REPLACE' command instead of 'INSERT'.
! 795:
! 796: =cut
! 797:
! 798: ###############################
! 799: sub replace_row {
! 800: my ($table_id,$rowdata) = @_;
! 801: #
! 802: return undef if (! defined(&connect_to_db()));
! 803: my $table_status = &check_table($table_id);
! 804: return undef if (! defined($table_status));
! 805: if (! $table_status) {
! 806: $errorstring = "table $table_id does not exist.";
! 807: return undef;
! 808: }
! 809: #
! 810: my $tablename = &translate_id($table_id);
! 811: #
! 812: my $sth;
! 813: if (exists($Tables{$tablename}->{'row_replace_sth'})) {
! 814: $sth = $Tables{$tablename}->{'row_replace_sth'};
! 815: } else {
! 816: # Build the insert statement handler
! 817: return undef if (! defined(&update_table_info($table_id)));
! 818: my $replace_request = 'REPLACE INTO '.$tablename.' VALUES(';
! 819: foreach (@{$Tables{$tablename}->{'Col_order'}}) {
! 820: $replace_request.="?,";
! 821: }
! 822: chop $replace_request;
! 823: $replace_request.=")";
! 824: $sth=$dbh->prepare($replace_request);
! 825: $Tables{$tablename}->{'row_replace_sth'}=$sth;
! 826: }
! 827: my @Parameters;
! 828: if (ref($rowdata) eq 'ARRAY') {
! 829: @Parameters = @$rowdata;
! 830: } elsif (ref($rowdata) eq 'HASH') {
! 831: foreach (@{$Tables{$tablename}->{'Col_order'}}) {
! 832: push(@Parameters,$rowdata->{$_});
! 833: }
! 834: }
! 835: $sth->execute(@Parameters);
! 836: if ($sth->err) {
! 837: $errorstring = "$dbh ATTEMPTED replace @Parameters RESULTING ERROR:\n".
! 838: $sth->errstr;
! 839: return undef;
! 840: }
! 841: $debugstring = "Stored row.";
! 842: return 1;
! 843: }
! 844:
1.1 matthew 845: ###########################################
846:
847: =pod
848:
1.8 matthew 849: =item &tables_in_db()
1.1 matthew 850:
851: Returns a list containing the names of all the tables in the database.
852: Returns undef on error.
853:
854: =cut
855:
856: ###########################################
857: sub tables_in_db {
1.3 matthew 858: return undef if (!defined(&connect_to_db()));
1.5 matthew 859: my $sth=$dbh->prepare('SHOW TABLES');
1.1 matthew 860: $sth->execute();
861: if ($sth->err) {
1.3 matthew 862: $errorstring = "$dbh ATTEMPTED:\n".'SHOW TABLES'.
863: "\nRESULTING ERROR:\n".$sth->errstr;
1.1 matthew 864: return undef;
865: }
866: my $aref = $sth->fetchall_arrayref;
867: my @table_list=();
868: foreach (@$aref) {
869: push @table_list,$_->[0];
870: }
871: $debugstring = "Got list of tables in DB: @table_list";
872: return @table_list;
873: }
874:
875: ###########################################
876:
877: =pod
878:
1.8 matthew 879: =item &translate_id()
1.1 matthew 880:
881: Used internally to translate a numeric table id into a MySQL table name.
882: If the input $id contains non-numeric characters it is assumed to have
883: already been translated.
884:
885: Checks are NOT performed to see if the table actually exists.
886:
887: =cut
888:
889: ###########################################
890: sub translate_id {
891: my $id = shift;
892: # id should be a digit. If it is not a digit we assume the given id
893: # is complete and does not need to be translated.
894: return $id if ($id =~ /\D/);
895: return $ENV{'user.name'}.'_'.$ENV{'user.domain'}.'_'.$id;
896: }
897:
898: ###########################################
899:
900: =pod
901:
1.8 matthew 902: =item &check_table()
903:
904: Input: table id
1.1 matthew 905:
906: Checks to see if the requested table exists. Returns 0 (no), 1 (yes), or
907: undef (error).
908:
909: =cut
910:
911: ###########################################
912: sub check_table {
913: my $table_id = shift;
1.3 matthew 914: return undef if (!defined(&connect_to_db()));
915: #
1.1 matthew 916: $table_id = &translate_id($table_id);
917: my @Table_list = &tables_in_db();
918: my $result = 0;
919: foreach (@Table_list) {
1.9 ! matthew 920: if ($_ eq $table_id) {
1.1 matthew 921: $result = 1;
922: last;
923: }
924: }
925: # If it does not exist, make sure we do not have it listed in %Tables
926: delete($Tables{$table_id}) if ((! $result) && exists($Tables{$table_id}));
927: $debugstring = "check_table returned $result for $table_id";
928: return $result;
929: }
930:
1.5 matthew 931: ###########################################
932:
933: =pod
934:
1.8 matthew 935: =item &remove_from_table()
936:
937: Input: $table_id, $column, $value
938:
939: Returns: the number of rows deleted. undef on error.
1.5 matthew 940:
941: Executes a "delete from $tableid where $column like binary '$value'".
942:
943: =cut
944:
945: ###########################################
946: sub remove_from_table {
947: my ($table_id,$column,$value) = @_;
948: return undef if (!defined(&connect_to_db()));
949: #
950: $table_id = &translate_id($table_id);
951: my $command = 'DELETE FROM '.$table_id.' WHERE '.$dbh->quote($column).
952: " LIKE BINARY ".$dbh->quote($value);
953: my $sth = $dbh->prepare($command);
954: $sth->execute();
955: if ($sth->err) {
956: $errorstring = "ERROR on execution of ".$command."\n".$sth->errstr;
957: return undef;
958: }
959: my $rows = $sth->rows;
960: return $rows;
961: }
962:
963:
1.1 matthew 964: 1;
965:
966: __END__;
1.5 matthew 967:
968: =pod
969:
970: =back
971:
972: =cut
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