Re: Upgraded SQLite: "database changed" error

It is indeed an interaction between Ima::DBI's use of prepare_cached and SQLite's changed error. Invalidating the $dbh->{CachedKids} is a passable work-around. I tried and failed to globally turn caching off in Ima::DBI::set_sql, but that probably would have caused performance issues anyway. I'm still not sure exactly which change revealed this problem.

DBD::SQLite seems to be the correct place to address this issue. Does anyone else have an opinion on that matter? Is there a better forum for DBD::SQLite discussions? The only other seems to be RT.

$dbh->{CachedKids} = {}; # after ANALYZE or similar

# from the example
$dbh->prepare_cached('select "hello" from a');
print Dump $dbh->{CachedKids},"\n";
$dbh->{CachedKids} = {};
$dbh->do("analyze");
my $sth = $dbh->prepare_cached('select "hello" from a');
print "got ", $dbh->selectrow_array($sth), "\n";
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A section of the DBI_TRACE from my main application

 T  <- prepare_cached('SELECT me.id
FROM   step me
WHERE  ( me.message = ? )  
' undef ...)= DBIx::ContextualFetch::st=HASH(0x8e09f38) at DBI.pm line
+ 381
 T  <- FETCH('Active')= '' at DBI.pm line 1139
 T  <- FETCH('Taint')= 1 at ContextualFetch.pm line 50
    <- STORE('Taint' 0)= 1 at ContextualFetch.pm line 51
    !! ERROR: 1 'database schema has changed(1) at dbdimp.c line 421' 
+(err#0)
    <- execute('Removing duplicates')= undef at ContextualFetch.pm lin
+e 52
       ERROR: 1 'database schema has changed(1) at dbdimp.c line 421' 
+(err#0)
    <> FETCH('Statement')= 'SELECT me.id
FROM   step me
WHERE  ( me.message = ? )  
' ('Statement' from cache) at DBI.pm line 1143
Val::Step can't SELECT me.id
FROM   step me
WHERE  ( me.message = ? )  
: DBD::SQLite::st execute failed: database schema has changed(1) at db
+dimp.c line 421 [for Statement "SELECT me.id
FROM   step me
WHERE  ( me.message = ? )  
"] at /usr/share/perl5/DBIx/ContextualFetch.pm line 52.
 at bin/validate.pl line 196
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Comment on Re: Upgraded SQLite: "database changed" error Select or Download Code

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Re^2: Upgraded SQLite: "database changed" error by jZed (Prior) on Jun 06, 2007 at 05:48 UTC
The dbi-users@perl.org mailing list is an appropriate place to discuss changes to DBDs and the most likely place other than rt.cpan.org for DBD authors to see your suggestions. Also, there may be similar issues with other DBDs so posting to the list might pull in some other ideas.	[reply]