lib/Bio/DB/GFF/Adaptor/dbi/pg_fts.pm

   1 package Bio::DB::GFF::Adaptor::dbi::pg_fts;
   2
   3
   4 =head1 NAME
   5
   6 Bio::DB::GFF::Adaptor::dbi::pg_fts -- Database adaptor for a specific postgres schema with a TSearch2 implementation
   7
   8 =head1 SYNOPSIS
   9
  10     #create new GFF database connection
  11     my $db      = Bio::DB::GFF->new( -adaptor => 'dbi::pg_fts',
  12                                      -dsn     => 'dbi:Pg:dbname=worm');
  13
  14     #add full text indexing 'stuff'
  15     #assumes that TSearch2 is available to PostgreSQL
  16     #this will take a VERY long time for a reasonably large database
  17     $db->install_TSearch2();
  18
  19     ...some time later...
  20     #we don't like full text searching...
  21     $db->remove_TSearch2();
  22
  23 =head1 DESCRIPTION
  24
  25 This adaptor is based on Bio::DB::GFF::Adaptor::dbi::pg but it implements
  26 the TSearch2 PostgreSQL contrib module for fast full text searching.  To
  27 use this module with your PostgreSQL GFF database, you need to make
  28 TSearch2 available in the database.
  29
  30 To use this adaptor, follow these steps:
  31
  32 =over
  33
  34 =item Install TSearch2 contrib module for Pg
  35
  36 Can be as easy as `sudo yum install postgresql-contrib`, or you may
  37 need to recompile PostgreSQL to include it.  See
  38 L<http://www.sai.msu.su/~megera/postgres/gist/tsearch/V2/docs/tsearch-V2-intro.html>
  39 for more details
  40
  41 =item Load the TSearch2 functions to you database
  42
  43   % cat tsearch2.sql | psql <your database>
  44
  45 =item Load your data using the pg adaptor:
  46
  47  % bp_pg_bulk_load_gff.pl -c -d yeast saccharomyces_cerevisiae.gff
  48
  49 or
  50
  51  % bp_load_gff.pl -c -d yeast -a dbi::pg saccharomyces_cerevisiae.gff
  52
  53 =item Add GFF/TSearch2 specific modifications
  54
  55 Execute a perl script like this one:
  56
  57   #!/usr/bin/perl -w
  58   use strict;
  59
  60   use Bio::DB::GFF;
  61
  62   my $db = Bio::DB::GFF->new(
  63       -adaptor   => 'dbi::pg_fts',
  64       -dsn       => 'dbi:Pg:dbname=yeast',
  65       -user      => 'scott',
  66     );
  67
  68   print "Installing TSearch2 columns...\n";
  69
  70   $db->install_TSearch2();
  71
  72   print "Done\n";
  73
  74 =back
  75
  76 Note that this last step will take a long time.  For a S. cerevisiae
  77 database with 15K rows, it took over an hour on my laptop, and
  78 with a C. elegans database (~10 million rows) it took well over a day.
  79
  80 If at some point you add more data you your database, you need to run
  81 a similar script to the one above, only executing the update_TSearch2()
  82 method.  Finally, if you want to remove the TSearch2 columns from your
  83 database and go back to using the pg adaptor, you can execute a script
  84 like the one above, only executing the remove_TSearch2() method.
  85
  86 =head1 NOTES ABOUT TSearch2 SEARCHING
  87
  88 You should know a few things about how searching with TSearch2 works in
  89 the GBrowse environment:
  90
  91 =over
  92
  93 =item 1
  94
  95 TSearch2 does not do wild cards, so you should encourage your users not
  96 to use them.  If wild cards are used, the adaptor will fall back on
  97 an ILIKE search, which will be much slower.
  98
  99 =item 2
 100
 101 However, TSearch2 does do 'word stemming'.  That is, if you search
 102 for 'copy', it will find 'copy', 'copies', and 'copied'.
 103
 104 =item 3
 105
 106 TSearch2 does not do phrase searching; all of the terms in the
 107 search string are ANDed together.
 108
 109 =back
 110
 111 =head1 ACKNOWLEDGEMENTS
 112
 113 Special thanks to Russell Smithies and Paul Smale at AgResearch in
 114 New Zealand for giving me their recipe for doing full text indexing
 115 in a GFF database.
 116
 117 =head1 BUGS
 118
 119 Please report bugs to the BioPerl and/or GBrowse mailing lists
 120 (L<mailto:bioperl-l@lists.open-bio.org> and L<mailto:gmod-gbrowse@lists.sourceforge.net>
 121 respectively).
 122
 123 =head1 SEE ALSO
 124
 125 Please see L<Bio::DB::GFF::Adaptor::dbi::pg> for more information
 126 about tuning your PostgreSQL server for GFF data, and for general
 127 information about GFF database access, see L<Bio::DB::GFF>.
 128
 129 =head1 AUTHOR
 130
 131 Scott Cain, cain@cshl.edu
 132
 133 =head1 APPENDIX
 134
 135 =cut
 136
 137 # a simple postgres adaptor
 138 use strict;
 139 use Bio::DB::GFF::Adaptor::dbi;
 140 use base qw(Bio::DB::GFF::Adaptor::dbi::pg);
 141
 142 use constant FULLTEXTSEARCH => <<END;
 143 SELECT distinct gclass,gname,fattribute_value,fmethod,fsource
 144     FROM fgroup,fattribute_to_feature,fdata,ftype
 145      WHERE fgroup.gid=fdata.gid
 146        AND fdata.fid=fattribute_to_feature.fid
 147        AND fdata.ftypeid=ftype.ftypeid
 148        AND (fattribute_to_feature.idxfti @@ to_tsquery('default', ?))
 149 END
 150 ;
 151
 152 use constant FULLTEXTWILDCARD => <<END;
 153 SELECT distinct gclass,gname,fattribute_value,fmethod,fsource
 154     FROM fgroup,fattribute_to_feature,fdata,ftype
 155      WHERE fgroup.gid=fdata.gid
 156        AND fdata.fid=fattribute_to_feature.fid
 157        AND fdata.ftypeid=ftype.ftypeid
 158        AND lower(fattribute_to_feature.fattribute_value) LIKE lower(?)
 159 END
 160 ;
 161
 162 sub new {
 163   my $class = shift;
 164   my $self  = $class->SUPER::new(@_);
 165   return $self;
 166 }
 167
 168 =head2 search_notes
 169
 170  Title   : search_notes
 171  Usage   : @search_results = $db->search_notes("full text string",$limit)
 172  Function: Search the notes for a text string, using PostgreSQL TSearch2
 173  Returns : array of results
 174  Args    : full text search string, and an optional row limit
 175  Status  : public
 176
 177 This is based on the mysql-specific method that makes use of the TSearch2
 178 functionality in PosgreSQL's contrib directory. Given a search string,
 179 it performs a full-text search of the notes table and returns an array
 180 of results.  Each row of the returned array is a arrayref containing
 181 the following fields:
 182
 183   column 1   A Bio::DB::GFF::Featname object, for passing to segment()
 184   column 2   The text of the note
 185   column 3   A relevance score.
 186
 187 =cut
 188
 189 sub search_notes {
 190   my $self = shift;
 191   my ($search_string,$limit) = @_;
 192
 193   my @terms = split /\s+/, $search_string;
 194
 195   my $sth;
 196   if ($search_string =~ /\*/) {
 197       $search_string =~ tr/*/%/s;
 198       my $query = FULLTEXTWILDCARD;
 199       $query   .= " limit $limit" if defined $limit;
 200       $sth      = $self->dbh->do_query($query,$search_string);
 201   }
 202   elsif (@terms == 1) {
 203       my $query = FULLTEXTSEARCH;
 204       $query   .= " limit $limit" if defined $limit;
 205       $sth      = $self->dbh->do_query($query,$search_string);
 206   }
 207   else {
 208       my $query = FULLTEXTSEARCH;
 209       my $andstring = join (' & ', @terms);
 210 #      $query   .= qq{ AND (fattribute_to_feature.fattribute_value ILIKE '\%$search_string%')};
 211       $query   .= " LIMIT $limit" if defined $limit;
 212       $sth      = $self->dbh->do_query($query,$andstring);
 213   }
 214
 215   my @results;
 216   while (my ($class,$name,$note,$method,$source) = $sth->fetchrow_array) {
 217
 218      next unless $class && $name;    # sorry, ignore NULL objects
 219      my $featname = Bio::DB::GFF::Featname->new($class=>$name);
 220      my $type     = Bio::DB::GFF::Typename->new($method,$source);
 221      push @results,[$featname,$note,0,$type]; #gbrowse expects a score, but
 222                                               #pg doesn't give one, thus the 0
 223   }
 224
 225   return @results;
 226 }
 227
 228 =head2 make_features_by_name_where_part
 229
 230  Title   : make_features_by_name_where_part
 231  Function: constructs a TSearch2-compliant WHERE clause for a name search
 232  Status  : protected
 233
 234 =cut
 235
 236 #need a make_features_by_name_where_part method to override pg
 237 sub make_features_by_name_where_part {
 238   my $self = shift;
 239   my ($class,$name) = @_;
 240
 241   my @terms = split /\s+/, $name;
 242
 243   if ($name =~ /\*/) {
 244     $name =~ tr/*/%/s;
 245     return ("fgroup.gclass=? AND lower(fgroup.gname) LIKE lower(?)",$class,$name);
 246   }
 247   else {
 248     my $where_str = "fgroup.gclass=? AND (fgroup.idxfti @@ to_tsquery('default', ?)) ";
 249     if (@terms == 1) {
 250       return ($where_str,$class,$name);
 251     }
 252     else {
 253       my $andstring = join (' & ', @terms);
 254 #      $where_str .= qq{ AND (fgroup.gname ILIKE '\%$name%')};
 255       return ($where_str,$class,$andstring);
 256     }
 257   }
 258 }
 259
 260 =head2 install_TSearch2
 261
 262  Title   : install_TSearch2
 263  Function: installs schema modifications for use with TSearch2
 264  Usage   : $db->install_TSearch2
 265  Status  : public
 266
 267 =cut
 268
 269
 270 #needs method for installing TSearch2 (does that mean that the SQL for
 271 #creating the tables and functions should go in here?  That would be
 272 #the safest and easiest thing to do
 273 sub install_TSearch2 {
 274   my $self = shift;
 275
 276   my $dbh = $self->features_db;
 277
 278   $dbh->do('ALTER TABLE fattribute_to_feature ADD COLUMN idxFTI tsvector')
 279      or $self->throw('adding FTI column to f_to_f failed');
 280
 281   $dbh->do('ALTER TABLE fgroup ADD COLUMN idxFTI tsvector')
 282      or $self->throw('adding FTI column to fgroup failed');
 283
 284   $self->update_TSearch2();
 285
 286   return;
 287 }
 288
 289 =head2 update_TSearch2
 290
 291  Title   : update_TSearch2
 292  Function: Updates TSearch2 columns
 293  Usage   : $db->update_TSearch2
 294  Status  : public
 295
 296 =cut
 297
 298
 299 sub update_TSearch2 {
 300   my $self = shift;
 301
 302   my $dbh = $self->features_db;
 303
 304   $self->warn('updating full text column; this may take a very long time...');
 305   $dbh->do("UPDATE fattribute_to_feature "
 306           ."SET idxFTI= to_tsvector('default', fattribute_value) "
 307           ."WHERE idxFTI IS NULL")
 308        or $self->throw('updating fti column failed');
 309   $dbh->do("UPDATE fgroup "
 310           ."SET idxFTI= to_tsvector('default', gname) "
 311           ."WHERE idxFTI IS NULL")
 312        or $self->throw('updating fgroup fti column failed');
 313
 314   $self->warn('Preliminary optimization of database; this may also take a long time...');
 315   $dbh->do('VACUUM FULL ANALYZE')
 316        or $self->throw('vacuum failed');
 317
 318   $self->warn('Updating full text index; again, this may take a long time');
 319   $dbh->do('CREATE INDEX idxFTI_idx ON fattribute_to_feature '
 320           .'USING gist(idxFTI)')
 321        or $self->warn('creating full text index failed');
 322   $dbh->do('CREATE INDEX fgroup_idxFTI_idx ON fgroup '
 323           .'USING gist(idxFTI)')
 324        or $self->warn('creating fgroup full text index failed');
 325
 326   $self->warn('Optimizing database; hopefully, this will not take as long as other steps');
 327   $dbh->do('VACUUM FULL ANALYZE');
 328   $dbh->do("SELECT set_curcfg('default')");
 329
 330   return;
 331 }
 332
 333 =head2 remove_TSearch2
 334
 335  Title   : remove_TSearch2
 336  Function: Removes TSearch2 columns
 337  Usage   : $db->remove_TSearch2
 338  Status  : public
 339
 340 =cut
 341
 342 sub remove_TSearch2 {
 343   my $self = shift;
 344
 345   my $dbh = $self->features_db;
 346
 347   $self->warn('Removing full text search capabilities');
 348   $dbh->do('DROP INDEX idxFTI_idx')
 349      or $self->throw('dropping full text index failed');
 350   $dbh->do('DROP INDEX fgroup_idxFTI_idx')
 351      or $self->throw('dropping full text index failed');
 352
 353   $dbh->do('ALTER TABLE fattribute_to_feature DROP COLUMN idxFTI')
 354      or $self->throw('dropping full text column failed');
 355   $dbh->do('ALTER TABLE fgroup DROP COLUMN idxFTI')
 356      or $self->throw('dropping full text column failed');
 357
 358
 359   return;
 360 }
 361
 362
 363 1;