use DBI;
use POSIX;
+use DBD::SQLite;
use Commods;
sub db_connect_core ($) {
my ($fn)= @_;
- my $h= DBI->connect("dbi:SQLite:$fn",'','',
- { AutoCommit=>0,
- RaiseError=>1, ShowErrorStatement=>1,
- unicode=>1 })
+ my $opts = { AutoCommit=>0,
+ RaiseError=>1, ShowErrorStatement=>1,
+ sqlite_unicode=>1 };
+
+ # DBI now wants to start a transaction whenever we even say
+ # SELECT. But this doesn't work if the DB is readonly. We can
+ # work around this by setting autocommit, in which case there is
+ # no need for a transaction for read-only db commands. Autocommit
+ # is (obviously) safe with readonly operations. But callers in
+ # yarrg do not specify to us whether they intend to write. So we
+ # decide, by looking at the file mode. And as belt-and-braces we
+ # set sqlite's own readonly flag as well.
+ # http://stackoverflow.com/questions/30082008/attempt-to-write-a-readonly-database-but-im-not
+ # http://stackoverflow.com/questions/35208727/can-sqlite-db-files-be-made-read-only
+ # http://cpansearch.perl.org/src/ISHIGAKI/DBD-SQLite-1.39/Changes
+ # (see entry for 1.38_01)
+ # http://stackoverflow.com/questions/17793672/perl-dbi-treats-setting-sqlite-db-cache-size-as-a-write-operation-when-subclassi
+ # https://rt.cpan.org/Public/Bug/Display.html?id=56444#
+ my $readonly =
+ (access $fn, POSIX::W_OK) ? 0 :
+ ($! == EACCES) ? 1 :
+ ($! == ENOENT) ? 0 :
+ die "$fn access(,W_OK) $!";
+ if ($readonly) {
+ $opts->{sqlite_open_flags} = DBD::SQLite::OPEN_READONLY;
+ $opts->{AutoCommit}=1;
+ }
+
+ my $h= DBI->connect("dbi:SQLite:$fn",'','',$opts)
or die "$fn $DBI::errstr ?";
return $h;
# default timeout is 30s which is plenty
if $ekindcount;
}
-sub db_check_referential_integrity () {
+sub db_check_referential_integrity ($) {
+ my ($full) = @_;
+ # non-full is done only for market data updates; it avoids
+ # detecting errors which are essentially missing metadata and
+ # old schemas, etc.
+
foreach my $bs (qw(buy sell)) {
nooutput(<<END);
# Every buy/sell must refer to an entry in commods, islands, and stalls:
- SELECT * FROM $bs NATURAL LEFT JOIN commods WHERE commodname IS NULL;
- SELECT * FROM $bs NATURAL LEFT JOIN islands WHERE islandname IS NULL;
- SELECT * FROM $bs LEFT JOIN STALLS USING (stallid) WHERE stallname IS NULL;
+ SELECT * FROM $bs LEFT JOIN commods USING (commodid) WHERE commodname IS NULL;
+ SELECT * FROM $bs LEFT JOIN islands USING (islandid) WHERE islandname IS NULL;
+ SELECT * FROM $bs LEFT JOIN stalls USING (stallid, islandid)
+ WHERE stallname IS NULL;
# Every buy/sell must be part of an upload:
- SELECT * FROM $bs NATURAL LEFT JOIN uploads WHERE timestamp IS NULL;
+ SELECT * FROM $bs LEFT JOIN uploads USING (islandid) WHERE timestamp IS NULL;
# The islandid in stalls must be the same as the islandid in buy/sell:
SELECT * FROM $bs JOIN stalls USING (stallid)
END
}
- foreach my $end (qw(aiid biid)) {
- foreach my $tab (qw(dists routes)) {
- nooutput(<<END);
+
+ nooutput(<<END);
+
+ # Every stall and upload must refer to an island:
+ SELECT * FROM stalls LEFT JOIN islands USING (islandid)
+ WHERE islandname IS NULL;
+ SELECT * FROM uploads LEFT JOIN islands USING (islandid)
+ WHERE islandname IS NULL;
+
+END
+ if ($full) {
+ foreach my $end (qw(aiid biid)) {
+ foreach my $tab (qw(dists routes)) {
+ nooutput(<<END);
# Every row in dists and routes must refer to two existing rows in islands:
SELECT * FROM $tab d LEFT JOIN islands ON d.$end=islandid
WHERE islandname IS NULL;
END
+ }
}
- }
- nooutput(<<END);
+ nooutput(<<END);
# Every pair of islands must have an entry in dists:
SELECT * FROM islands ia JOIN islands ib LEFT JOIN dists
ON ia.islandid=aiid and ib.islandid=biid
WHERE dist IS NULL;
- # Every stall and upload must refer to an island:
- SELECT * FROM stalls NATURAL LEFT JOIN islands WHERE islandname IS NULL;
- SELECT * FROM uploads NATURAL LEFT JOIN islands WHERE islandname IS NULL;
-
# Every commod must refers to a commodclass and vice versa:
- SELECT * FROM commods NATURAL LEFT JOIN commodclasses
+ SELECT * FROM commods LEFT JOIN commodclasses USING (commodclassid)
WHERE commodclass IS NULL;
- SELECT * FROM commodclasses NATURAL LEFT JOIN commods
+ SELECT * FROM commodclasses LEFT JOIN commods USING (commodclassid)
WHERE commodname IS NULL;
# Ordvals which are not commodclass ordvals are unique:
# For every class, posinclass is dense from 1 to maxposinclass,
# apart from the commods for which it is zero.
SELECT commodclass,commodclassid,posinclass,count(*)
- FROM commods NATURAL JOIN commodclasses
+ FROM commods JOIN commodclasses USING (commodclassid)
WHERE posinclass > 0
GROUP BY commodclassid,posinclass
HAVING count(*) > 1;
SELECT commodclass,commodclassid,count(*)
- FROM commods NATURAL JOIN commodclasses
+ FROM commods JOIN commodclasses USING (commodclassid)
WHERE posinclass > 0
GROUP BY commodclassid
HAVING count(*) != maxposinclass;
SELECT *
- FROM commods NATURAL JOIN commodclasses
+ FROM commods JOIN commodclasses USING (commodclassid)
WHERE posinclass < 0 OR posinclass > maxposinclass;
END
+ }
}
-sub db_chkcommit () {
- db_check_referential_integrity();
+sub db_chkcommit ($) {
+ my ($full) = @_;
+ db_check_referential_integrity($full);
$dbh->commit();
}