script to run a single query across several databases

can be run across several hosts at a time

misc-scripts/multidb_sql.pl

+#!/usr/bin/env perl
+
+###############################################################################################################
+# multidb_sql script
+# given a pattern of databases to query, runs a query accross all databases
+# can take a file as input, to apply sql without printing out results
+# USAGE : perl multidb_sql.pl -dbpattern _core_ -expr "select count(*) from gene"
+################################################################################################################
+
+
+
+
+use strict;
+use DBI;
+use Getopt::Long;
+
+my ( @hosts, $host, $user, $pass, $port, $expression, $dbpattern, $file, $result_only ); 
+
+$user = 'ensro' ;  
+$pass = '' ;
+$port = 3306 ;  
+@hosts = qw ( ens-staging1 ens-staging2) ;
+
+GetOptions( "host|dbhost=s", \$host,
+            "hosts|dbhosts=s", \@hosts,
+	    "user|dbuser=s", \$user,
+	    "pass|dbpass=s", \$pass,
+	    "port|dbport=i", \$port,
+	    "expr=s", \$expression,
+	    "file=s", \$file,
+	    "dbpattern|pattern=s", \$dbpattern,
+            "result_only!", \$result_only,
+	  );
+
+if ($host) {
+  @hosts = $host ;
+}
+else {
+  @hosts = split(/,/,join(',',@hosts)) ;
+}
+
+foreach my $host ( @hosts ) {
+  my $dsn = "DBI:mysql:host=$host";
+  if( $port ) {
+    $dsn .= ";port=$port";
+  }
+
+  my @expressions;
+
+  if( $file ) {
+    local *FH;
+    if( ! -r $file ) {
+      die ( "File $file not readable" );
+    }
+    open( FH, "<$file" );
+    my $exp;
+    while( my $line = <FH> ) {
+      if( $line =~ /;$/ ) {
+        $line =~ s/;$//;
+        $exp .= " ".$line;
+        push( @expressions, $exp );
+        $exp = "";
+      } else {
+        $exp .= " ".$line;
+      }
+    }
+    if( $exp ) {
+      push( @expressions, $exp );
+    }  
+    close FH;
+  }
+
+  my $db = DBI->connect( $dsn, $user, $pass );
+  my @dbnames = map {$_->[0] } @{ $db->selectall_arrayref( "show databases" ) };
+  for my $dbname ( @dbnames) {   
+    next if ( $dbname !~ /$dbpattern/ );
+    unless ($result_only) { 
+      print  "$dbname\n";
+    }
+    if(( ! $expression ) && ( !$file )) {
+      next;
+    }
+  
+    $db->do( "use $dbname" );
+    if( $file ) {
+      for my $sql ( @expressions ) {
+        print STDERR "Do $sql\n";
+        $db->do( $sql );
+      }  
+    } elsif( $expression =~ /^\s*select/i || $expression =~ /^\s*show/i || $expression =~ /^\s*desc/i ) {
+      my $res = $db->selectall_arrayref( $expression );
+      my @results = map { join( " ", @$_ ) } @$res ;
+      my $db_name_off = 0 ;
+      for my $result ( @results ) {
+        if($result_only){ 
+          unless ($db_name_off){
+            $db_name_off =1 ;
+            print  "==> $dbname :\n";
+          }
+        }
+        print  "    Result: ",$result,"\n";
+      }
+    } else {
+      $db->do( $expression );
+      print  "  done.\n";
+    }
+  }  
+}
+
+sub usage {
+  print STDERR <<EOF
+
+             Usage: multidb_sql options
+ Where options are: -host hostname 
+                    -user username 
+                    -pass password 
+                    -port port_of_server optional
+                    -dbpattern regular expression that the database name has to match
+                    -expr sql statement you want to execute. 
+                          if omitted, just print database names matching
+                          if select, show or describe prints results
+                    -file Apply sql in file to all databases. Does not print results.
+                    -result_only only prints out databases for which results where found
+
+EOF
+;
+  exit;
+}
+