#
# Library functions for the NewsStats package.
#
-# Copyright (c) 2010 Thomas Hochstein <thh@inter.net>
+# Copyright (c) 2010-2012 Thomas Hochstein <thh@inter.net>
#
# This module can be redistributed and/or modified under the same terms under
# which Perl itself is published.
require Exporter;
@ISA = qw(Exporter);
@EXPORT = qw(
- $MySelf
$MyVersion
$PackageVersion
- ReadOptions
+ $FullPath
+ $HomePath
+ ShowVersion
+ ShowPOD
ReadConfig
OverrideConfig
InitDB
+ Bleat
);
@EXPORT_OK = qw(
GetTimePeriod
LastMonth
- CheckMonth
SplitPeriod
ListMonth
ListNewsgroups
+ ParseHierarchies
ReadGroupList
OutputData
FormatOutput
SQLHierarchies
+ SQLSortOrder
SQLGroupList
- GetMaxLenght
+ SQLSetBounds
+ SQLBuildClause
+ GetMaxLength
);
-%EXPORT_TAGS = ( TimePeriods => [qw(GetTimePeriod LastMonth CheckMonth SplitPeriod ListMonth)],
+%EXPORT_TAGS = ( TimePeriods => [qw(GetTimePeriod LastMonth SplitPeriod
+ ListMonth)],
Output => [qw(OutputData FormatOutput)],
- SQLHelper => [qw(SQLHierarchies SQLGroupList GetMaxLenght)]);
+ SQLHelper => [qw(SQLHierarchies SQLSortOrder SQLGroupList
+ SQLSetBounds SQLBuildClause GetMaxLength)]);
$VERSION = '0.01';
our $PackageVersion = '0.01';
use Data::Dumper;
use File::Basename;
-use Getopt::Std;
use Config::Auto;
use DBI;
#####-------------------------------- Vars --------------------------------#####
-our $MySelf = fileparse($0, '.pl');
-our $MyVersion = "$MySelf $::VERSION (NewsStats.pm $VERSION)";
+# trim the path
+our $FullPath = $0;
+our $HomePath = dirname($0);
+$0 =~ s%.*/%%;
+# set version string
+our $MyVersion = "$0 $::VERSION (NewsStats.pm $VERSION)";
#####------------------------------- Basics -------------------------------#####
-################################################################################
-sub ReadOptions {
-################################################################################
-### read commandline options and act on standard options -h and -V
-### IN : $Params: list of legal commandline paramaters (without -h and -V)
-### OUT: a hash containing the commandline options
- $Getopt::Std::STANDARD_HELP_VERSION = 1;
-
- my ($Params) = @_;
- my %Options;
-
- getopts('Vh'.$Params, \%Options);
-
- # -V: display version
- &ShowVersion if ($Options{'V'});
-
- # -h: feed myself to perldoc
- &ShowPOD if ($Options{'h'});
-
- return %Options;
-};
################################################################################
################################################################################
sub ShowVersion {
################################################################################
### display version and exit
- print "NewsStats v$PackageVersion\n$MyVersion\nCopyright (c) 2010 Thomas Hochstein <thh\@inter.net>\n";
- print "This program is free software; you may redistribute it and/or modify it under the same terms as Perl itself.\n";
+ print "NewsStats v$PackageVersion\n$MyVersion\n";
+ print "Copyright (c) 2010-2012 Thomas Hochstein <thh\@inter.net>\n";
+ print "This program is free software; you may redistribute it ".
+ "and/or modify it under the same terms as Perl itself.\n";
exit(100);
};
################################################################################
sub ShowPOD {
################################################################################
### feed myself to perldoc and exit
- exec('perldoc', $0);
+ exec('perldoc', $FullPath);
exit(100);
};
################################################################################
################################################################################
################################################################################
-sub OverrideConfig {
+sub OverrideConfig {
################################################################################
### override configuration values
### IN : $ConfigR : reference to configuration hash
my ($ConfigR,$OverrideR) = @_;
my %Override = %$OverrideR;
# Config hash empty?
- warn "$MySelf W: Empty configuration hash passed to OverrideConfig().\n" if ( keys %$ConfigR < 1);
+ &Bleat(1,"Empty configuration hash passed to OverrideConfig()")
+ if ( keys %$ConfigR < 1);
# return if no overrides
return if (keys %Override < 1 or keys %$ConfigR < 1);
foreach my $Key (keys %Override) {
### OUT: DBHandle
my ($ConfigR,$Die) = @_;
my %Conf = %$ConfigR;
- my $DBHandle = DBI->connect(sprintf('DBI:%s:database=%s;host=%s',$Conf{'DBDriver'},$Conf{'DBDatabase'},$Conf{'DBHost'}), $Conf{'DBUser'}, $Conf{'DBPw'}, { PrintError => 0 });
+ my $DBHandle = DBI->connect(sprintf('DBI:%s:database=%s;host=%s',
+ $Conf{'DBDriver'},$Conf{'DBDatabase'},
+ $Conf{'DBHost'}), $Conf{'DBUser'},
+ $Conf{'DBPw'}, { PrintError => 0 });
if (!$DBHandle) {
- die ("$MySelf: E: $DBI::errstr\n") if (defined($Die) and $Die);
- warn("$MySelf: W: $DBI::errstr\n");
+ &Bleat(2,$DBI::errstr) if (defined($Die) and $Die);
+ &Bleat(1,$DBI::errstr);
};
return $DBHandle;
};
################################################################################
+################################################################################
+sub Bleat {
+################################################################################
+### print warning or error messages and terminate in case of error
+### IN : $Level : 1 = warning, 2 = error
+### $Message: warning or error message
+ my ($Level,$Message) = @_;
+ if ($Level == 1) {
+ warn "$0 W: $Message\n"
+ } elsif ($Level == 2) {
+ die "$0 E: $Message\n"
+ } else {
+ print "$0: $Message\n"
+ }
+};
+################################################################################
+
#####------------------------------ GetStats ------------------------------#####
################################################################################
### OUT: \%ValidGroups: hash containing all valid newsgroups
my ($Filename) = @_;
my %ValidGroups;
- open (my $LIST,"<$Filename") or die "$MySelf: E: Cannot read $Filename: $!\n";
+ open (my $LIST,"<$Filename") or &Bleat(2,"Cannot read $Filename: $!");
while (<$LIST>) {
- s/^(\S+).*$/$1/;
+ s/^\s*(\S+).*$/$1/;
chomp;
+ next if /^$/;
$ValidGroups{$_} = '1';
};
close $LIST;
################################################################################
sub GetTimePeriod {
################################################################################
-### get a time period to act on, in order of preference: by default the
-### last month; or a month submitted by -m YYYY-MM; or a time period submitted
-### by -p YYYY-MM:YYYY-MM
-### IN : $Month,$Period: contents of -m and -p
-### OUT: $StartMonth, $EndMonth (identical if period is just one month)
- my ($Month,$Period) = @_;
- # exit if -m is set and not like YYYY-MM
- die "$MySelf: E: Wrong date format - use '$MySelf -m YYYY-MM'!\n" if not &CheckMonth($Month);
- # warn if -m and -p is set
- warn "$MySelf: W: Time period assigned by '-p' takes precendece over month assigned by '-m'.\n" if ($Month && $Period);
- # default: set -m to last month
- $Month = &LastMonth if (!defined($Month) and !defined($Period));
- # set $StartMonth, $EndMonth
- my ($StartMonth, $EndMonth);
- if ($Period) {
- # -p: get date range
- ($StartMonth, $EndMonth) = &SplitPeriod($Period);
- die "$MySelf: E: Wrong format for time period - use '$MySelf -p YYYY-MM:YYYY-MM'!\n" if !defined($StartMonth);
+### get a time period to act on from --month option;
+### if empty, default to last month
+### IN : $Month: may be empty, 'YYYY-MM', 'YYYY-MM:YYYY-MM' or 'all'
+### OUT: $Verbal,$SQL: verbal description and WHERE-clause
+### of the chosen time period
+ my ($Month) = @_;
+ # define result variables
+ my ($Verbal, $SQL);
+ # define a regular expression for a month
+ my $REMonth = '\d{4}-\d{2}';
+
+ # default to last month if option is not set
+ if(!$Month) {
+ $Month = &LastMonth;
+ }
+
+ # check for valid input
+ if ($Month =~ /^$REMonth$/) {
+ # single month (YYYY-MM)
+ ($Month) = &CheckMonth($Month);
+ $Verbal = $Month;
+ $SQL = sprintf("month = '%s'",$Month);
+ } elsif ($Month =~ /^$REMonth:$REMonth$/) {
+ # time period (YYYY-MM:YYYY-MM)
+ $Verbal = sprintf('%s to %s',&SplitPeriod($Month));
+ $SQL = sprintf("month BETWEEN '%s' AND '%s'",&SplitPeriod($Month));
+ } elsif ($Month =~ /^all$/i) {
+ # special case: ALL
+ $Verbal = 'all time';
+ $SQL = '';
} else {
- # set $StartMonth = $EndMonth = $Month if -p is not set
- $StartMonth = $EndMonth = $Month;
- };
- return ($StartMonth, $EndMonth);
+ # invalid input
+ return (undef,undef);
+ }
+
+ return ($Verbal,$SQL);
};
################################################################################
################################################################################
sub CheckMonth {
################################################################################
-### check if input is a valid month in YYYY-MM form
-### IN : $Month: month
-### OUT: TRUE / FALSE
- my ($Month) = @_;
- return 0 if (defined($Month) and $Month !~ /^\d{4}-\d{2}$/);
- return 1;
+### check if input (in YYYY-MM form) is valid with MM between 01 and 12;
+### otherwise, fix it
+### IN : @Month: array of month
+### OUT: @Month: a valid month
+ my (@Month) = @_;
+ foreach my $Month (@Month) {
+ my ($OldMonth) = $Month;
+ my ($CalMonth) = substr ($Month, -2);
+ if ($CalMonth < 1 or $CalMonth > 12) {
+ $CalMonth = '12' if $CalMonth > 12;
+ $CalMonth = '01' if $CalMonth < 1;
+ substr($Month, -2) = $CalMonth;
+ &Bleat(1,sprintf("'%s' is an invalid date (MM must be between '01' ".
+ "and '12'), set to '%s'.",$OldMonth,$Month));
+ }
+ }
+ return @Month;
};
################################################################################
################################################################################
### split a time period denoted by YYYY-MM:YYYY-MM into start and end month
### IN : $Period: time period
-### OUT: $StartMonth, Â$EndMonth
+### OUT: $StartMonth, $EndMonth
my ($Period) = @_;
- return (undef,undef) if $Period !~ /^\d{4}-\d{2}:\d{4}-\d{2}$/;
my ($StartMonth, $EndMonth) = split /:/, $Period;
+ ($StartMonth,$EndMonth) = CheckMonth($StartMonth,$EndMonth);
# switch parameters as necessary
if ($EndMonth gt $StartMonth) {
return ($StartMonth, $EndMonth);
sub ListMonth {
################################################################################
### return a list of months (YYYY-MM) between start and end month
-### IN : $StartMonth, $EndMonth
-### OUT: @Months: array containing all months from $StartMonth to $EndMonth
- my ($StartMonth, $EndMonth) = @_;
- return (undef,undef) if ($StartMonth !~ /^\d{4}-\d{2}$/ or $EndMonth !~ /^\d{4}-\d{2}$/);
- # return if $StartMonth = $EndMonth
- return ($StartMonth) if ($StartMonth eq $EndMonth);
+### IN : $MonthExpression ('YYYY-MM' or 'YYYY-MM to YYYY-MM')
+### OUT: @Months: array containing all months from $MonthExpression enumerated
+ my ($MonthExpression )= @_;
+ # return if single month
+ return ($MonthExpression) if ($MonthExpression =~ /^\d{4}-\d{2}$/);
+ # parse $MonthExpression
+ my ($StartMonth, $EndMonth) = split(' to ',$MonthExpression);
# set $Year, $Month from $StartMonth
my ($Year, $Month) = split /-/, $StartMonth;
# define @Months
sub OutputData {
################################################################################
### read database query results from DBHandle and print results with formatting
-### IN : $Format : format specifier
-### $FileName: file name template (-f): filename-YYYY-MM
-### $DBQuery : database query handle with executed query,
+### IN : $Format : format specifier
+### $Comments : print or suppress all comments for machine-readable output
+### $GroupBy : primary sorting order (month or key)
+### $Precision: number of digits right of decimal point (0 or 2)
+### $ValidKeys: reference to a hash containing all valid keys
+### $FileTempl: file name template (--filetemplate): filetempl-YYYY-MM
+### $DBQuery : database query handle with executed query,
### containing $Month, $Key, $Value
-### $PadGroup: padding length for newsgroups field (optional) for 'pretty'
- my ($Format, $FileName, $DBQuery, $PadGroup) = @_;
- my ($Handle, $OUT);
+### $PadGroup : padding length for key field (optional) for 'pretty'
+ my ($Format, $Comments, $GroupBy, $Precision, $ValidKeys, $FileTempl,
+ $DBQuery, $PadGroup) = @_;
+ my %ValidKeys = %{$ValidKeys} if $ValidKeys;
+ my ($FileName, $Handle, $OUT);
our $LastIteration;
+
+ # define output types
+ my %LegalOutput;
+ @LegalOutput{('dump',,'list','pretty')} = ();
+ # bail out if format is unknown
+ &Bleat(2,"Unknown output type '$Format'!") if !exists($LegalOutput{$Format});
+
while (my ($Month, $Key, $Value) = $DBQuery->fetchrow_array) {
+ # don't display invalid keys
+ if(%ValidKeys and !defined($ValidKeys{$Key})) {
+ # FIXME
+ # &Bleat(1,sprintf("DROPPED: %s",$Key));
+ next;
+ };
+ # care for correct sorting order and abstract from month and keys:
+ # $Caption will be $Month or $Key, according to sorting order,
+ # and $Key will be $Key or $Month, respectively
+ my $Caption;
+ if ($GroupBy eq 'key') {
+ $Caption = $Key;
+ $Key = $Month;
+ } else {
+ $Caption = $Month;
+ }
# set output file handle
- if (!$FileName) {
+ if (!$FileTempl) {
$Handle = *STDOUT{IO}; # set $Handle to a reference to STDOUT
- } elsif (!defined($LastIteration) or $LastIteration ne $Month) {
+ } elsif (!defined($LastIteration) or $LastIteration ne $Caption) {
close $OUT if ($LastIteration);
- open ($OUT,sprintf('>%s-%s',$FileName,$Month)) or die sprintf("$MySelf: E: Cannot open output file '%s-%s': $!\n",$FileName,$Month);
+ # safeguards for filename creation:
+ # replace potential problem characters with '_'
+ $FileName = sprintf('%s-%s',$FileTempl,$Caption);
+ $FileName =~ s/[^a-zA-Z0-9_-]+/_/g;
+ open ($OUT,">$FileName")
+ or &Bleat(2,sprintf("Cannot open output file '%s': $!",
+ $FileName));
$Handle = $OUT;
};
- print $Handle &FormatOutput($Format, $Month, $Key, $Value, $PadGroup);
- $LastIteration = $Month;
+ print $Handle &FormatOutput($Format, $Comments, $Caption, $Key, $Value,
+ $Precision, $PadGroup);
+ $LastIteration = $Caption;
};
- close $OUT if ($FileName);
+ close $OUT if ($FileTempl);
};
################################################################################
sub FormatOutput {
################################################################################
### format information for output according to format specifier
-### IN : $Format : format specifier
-### $Month : month (as YYYY-MM)
-### $Key : newsgroup, client, ...
-### $Value : number of postings with that attribute
-### $PadGroup: padding length for key field (optional) for 'pretty'
+### IN : $Format : format specifier
+### $Comments : print or suppress all comments for machine-readable output
+### $Caption : month (as YYYY-MM) or $Key, according to sorting order
+### $Key : newsgroup, client, ... or $Month, as above
+### $Value : number of postings with that attribute
+### $Precision: number of digits right of decimal point (0 or 2)
+### $PadGroup : padding length for key field (optional) for 'pretty'
### OUT: $Output: formatted output
- my ($Format, $Month, $Key, $Value, $PadGroup) = @_;
-
- # define output types
- my %LegalOutput;
- @LegalOutput{('dump','dumpgroup','list','pretty')} = ();
- # bail out if format is unknown
- die "$MySelf: E: Unknown output type '$Format'!\n" if !exists($LegalOutput{$Format});
-
+ my ($Format, $Comments, $Caption, $Key, $Value, $Precision, $PadGroup) = @_;
my ($Output);
- # keep last month in mind
+ # keep last caption in mind
our ($LastIteration);
+ # create one line of output
if ($Format eq 'dump') {
- # output as dump (ng nnnnn)
- $Output = sprintf ("%s %u\n",$Key,$Value);
- } elsif ($Format eq 'dumpgroup') {
- # output as dump (YYYY-NN: nnnnn)
- $Output = sprintf ("%s: %5u\n",$Month,$Value);
+ # output as dump (key value)
+ $Output = sprintf ("# %s:\n",$Caption)
+ if ($Comments and (!defined($LastIteration) or $Caption ne $LastIteration));
+ $Output .= sprintf ("%s %u\n",$Key,$Value);
} elsif ($Format eq 'list') {
- # output as list (YYYY-NN: ng nnnnn)
- $Output = sprintf ("%s: %s %u\n",$Month,$Key,$Value);
+ # output as list (caption key value)
+ $Output = sprintf ("%s %s %u\n",$Caption,$Key,$Value);
} elsif ($Format eq 'pretty') {
- # output as table
- $Output = sprintf ("----- %s:\n",$Month) if (!defined($LastIteration) or $Month ne $LastIteration);
- $LastIteration = $Month;
- $Output .= sprintf ($PadGroup ? sprintf("%%-%us %%5u\n",$PadGroup) : "%s %u\n",$Key,$Value);
+ # output as a table
+ $Output = sprintf ("# ----- %s:\n",$Caption)
+ if ($Comments and (!defined($LastIteration) or $Caption ne $LastIteration));
+ $Output .= sprintf ($PadGroup ? sprintf("%%-%us %%10.*f\n",$PadGroup) :
+ "%s %.*f\n",$Key,$Precision,$Value);
};
return $Output;
};
### IN : $ShowHierarchies: boolean value
### OUT: SQL code
my ($ShowHierarchies) = @_;
- return $ShowHierarchies ? '' : "AND newsgroup NOT LIKE '%.ALL'";
+ return $ShowHierarchies ? '' : "newsgroup NOT LIKE '%.ALL'";
};
################################################################################
-sub GetMaxLenght {
+sub GetMaxLength {
################################################################################
### get length of longest field in future query result
-### IN : $DBHandle : database handel
-### $Table : table to query
-### $Field : field to check
-### $WhereClause: WHERE clause
-### @BindVars : bind variables for WHERE clause
+### IN : $DBHandle : database handel
+### $Table : table to query
+### $Field : field to check
+### $WhereClause : WHERE clause
+### $HavingClause: HAVING clause
+### @BindVars : bind variables for WHERE clause
### OUT: $Length: length of longest instnace of $Field
- my ($DBHandle,$Table,$Field,$WhereClause,@BindVars) = @_;
- my $DBQuery = $DBHandle->prepare(sprintf("SELECT MAX(LENGTH(%s)) FROM %s WHERE %s",$Field,$Table,$WhereClause));
- $DBQuery->execute(@BindVars) or warn sprintf("$MySelf: W: Can't get field length for %s from table %s: $DBI::errstr\n",$Field,$Table);
+ my ($DBHandle,$Table,$Field,$WhereClause,$HavingClause,@BindVars) = @_;
+ my $DBQuery = $DBHandle->prepare(sprintf("SELECT MAX(LENGTH(%s)) ".
+ "FROM %s %s %s",$Field,$Table,
+ $WhereClause,$HavingClause ?
+ 'GROUP BY newsgroup' . $HavingClause .
+ ' ORDER BY LENGTH(newsgroup) '.
+ 'DESC LIMIT 1': ''));
+ $DBQuery->execute(@BindVars) or &Bleat(1,sprintf("Can't get field length ".
+ "for '%s' from table '%s': ".
+ "$DBI::errstr",$Field,$Table));
my ($Length) = $DBQuery->fetchrow_array;
return $Length;
};
+################################################################################
+sub SQLSortOrder {
+################################################################################
+### build a SQL 'ORDER BY' clause from $OptGroupBy (primary sorting) and
+### $OptOrderBy (secondary sorting), both ascending or descending;
+### descending sorting order is done by adding '-desc'
+### IN : $GroupBy: primary sort by 'month' (default) or 'newsgroups'
+### $OrderBy: secondary sort by month/newsgroups (default)
+### or number of 'postings'
+### OUT: a SQL ORDER BY clause
+ my ($GroupBy,$OrderBy) = @_;
+ my ($GroupSort,$OrderSort) = ('','');
+ # $GroupBy (primary sorting)
+ if (!$GroupBy) {
+ $GroupBy = 'month';
+ } else {
+ ($GroupBy, $GroupSort) = SQLParseOrder($GroupBy);
+ if ($GroupBy =~ /group/i) {
+ $GroupBy = 'newsgroup';
+ } else {
+ $GroupBy = 'month';
+ }
+ }
+ my $Secondary = ($GroupBy eq 'month') ? 'newsgroup' : 'month';
+ # $OrderBy (secondary sorting)
+ if (!$OrderBy) {
+ $OrderBy = $Secondary;
+ } else {
+ ($OrderBy, $OrderSort) = SQLParseOrder($OrderBy);
+ if ($OrderBy =~ /posting/i) {
+ $OrderBy = "postings $OrderSort, $Secondary";
+ } else {
+ $OrderBy = "$Secondary $OrderSort";
+ }
+ }
+ return ($GroupBy,&SQLBuildClause('order',"$GroupBy $GroupSort",$OrderBy));
+};
+
+################################################################################
+sub SQLParseOrder {
+################################################################################
+### parse $OptGroupBy or $OptOrderBy option of the form param[-desc], e.g.
+### 'month', 'month-desc', 'newsgroups-desc', but also just 'desc'
+### IN : $OrderOption: order option (see above)
+### OUT: parameter to sort by,
+### sort order ('DESC' or nothing, meaning 'ASC')
+ my ($OrderOption) = @_;
+ my $SortOrder = '';
+ if ($OrderOption =~ s/-?desc$//i) {
+ $SortOrder = 'DESC';
+ } else {
+ $OrderOption =~ s/-?asc$//i
+ }
+ return ($OrderOption,$SortOrder);
+};
+
################################################################################
sub SQLGroupList {
################################################################################
-### explode list of newsgroups separated by : (with wildcards) to a SQL WHERE
-### clause
+### explode list of newsgroups separated by : (with wildcards)
+### to a SQL 'WHERE' expression
### IN : $Newsgroups: list of newsgroups (group.one.*:group.two:group.three.*)
-### OUT: SQL code, list of newsgroups
+### OUT: SQL code to become part of a 'WHERE' clause,
+### list of newsgroups for SQL bindings
my ($Newsgroups) = @_;
+ # substitute '*' wildcard with SQL wildcard character '%'
$Newsgroups =~ s/\*/%/g;
- return ('newsgroup LIKE ?', $Newsgroups) if $Newsgroups !~ /:/;
+ # just one newsgroup?
+ return (SQLGroupWildcard($Newsgroups),$Newsgroups) if $Newsgroups !~ /:/;
+ # list of newsgroups separated by ':'
my $SQL = '(';
my @GroupList = split /:/, $Newsgroups;
foreach (@GroupList) {
$SQL .= ' OR ' if $SQL gt '(';
- $SQL .= 'newsgroup LIKE ?';
+ $SQL .= SQLGroupWildcard($_);
};
$SQL .= ')';
return ($SQL,@GroupList);
};
+################################################################################
+sub SQLGroupWildcard {
+################################################################################
+### build a valid SQL 'WHERE' expression with or without wildcards
+### IN : $Newsgroup: newsgroup expression, probably with wildcard
+### (group.name or group.name.%)
+### OUT: SQL code to become part of a 'WHERE' clause
+ my ($Newsgroup) = @_;
+ # FIXME: check for validity
+ if ($Newsgroup !~ /%/) {
+ return 'newsgroup = ?';
+ } else {
+ return 'newsgroup LIKE ?';
+ }
+};
+
+################################################################################
+sub SQLSetBounds {
+################################################################################
+### set upper and/or lower boundary (number of postings)
+### IN : $Type: 'level', 'average', 'sum' or 'default'
+### $LowBound,$UppBound: lower/upper boundary, respectively
+### OUT: SQL code to become part of a WHERE or HAVING clause
+ my ($Type,$LowBound,$UppBound) = @_;
+ ($LowBound,$UppBound) = SQLCheckNumber($LowBound,$UppBound);
+ if($LowBound and $UppBound and $LowBound > $UppBound) {
+ &Bleat(1,"Lower boundary $LowBound is larger than Upper boundary ".
+ "$UppBound, exchanging boundaries.");
+ ($LowBound,$UppBound) = ($UppBound,$LowBound);
+ }
+ # default to 'default'
+ my $WhereHavingFunction = 'postings';
+ # set $LowBound to SQL statement:
+ # 'WHERE postings >=', 'HAVING MIN(postings) >=' or 'HAVING AVG(postings) >='
+ if ($Type eq 'level') {
+ $WhereHavingFunction = 'MIN(postings)'
+ } elsif ($Type eq 'average') {
+ $WhereHavingFunction = 'AVG(postings)'
+ } elsif ($Type eq 'sum') {
+ $WhereHavingFunction = 'SUM(postings)'
+ }
+ $LowBound = sprintf('%s >= '.$LowBound,$WhereHavingFunction) if ($LowBound);
+ # set $LowBound to SQL statement:
+ # 'WHERE postings <=', 'HAVING MAX(postings) <=' or 'HAVING AVG(postings) <='
+ if ($Type eq 'level') {
+ $WhereHavingFunction = 'MAX(postings)'
+ } elsif ($Type eq 'average') {
+ $WhereHavingFunction = 'AVG(postings)'
+ } elsif ($Type eq 'sum') {
+ $WhereHavingFunction = 'SUM(postings)'
+ }
+ $UppBound = sprintf('%s <= '.$UppBound,$WhereHavingFunction) if ($UppBound);
+ return ($LowBound,$UppBound);
+};
+
+################################################################################
+sub SQLCheckNumber {
+################################################################################
+### check if input is a valid positive integer; otherwise, make it one
+### IN : @Numbers: array of parameters
+### OUT: @Numbers: a valid positive integer
+ my (@Numbers) = @_;
+ foreach my $Number (@Numbers) {
+ if ($Number and $Number < 0) {
+ &Bleat(1,"Boundary $Number is < 0, set to ".-$Number);
+ $Number = -$Number;
+ }
+ $Number = '' if ($Number and $Number !~ /^\d+$/);
+ }
+ return @Numbers;
+};
+
+################################################################################
+sub SQLBuildClause {
+################################################################################
+### build a valid SQL WHERE, GROUP BY, ORDER BY or HAVING clause
+### from multiple expressions which *may* be empty
+### IN : $Type: 'where', 'having', 'group' or 'order'
+### @Expressions: array of expressions
+### OUT: $SQLClause: a SQL clause
+ my ($Type,@Expressions) = @_;
+ my ($SQLClause,$Separator,$Statement);
+ # set separator ('AND' or ',')
+ if ($Type eq 'where' or $Type eq 'having') {
+ $Separator = 'AND';
+ } else {
+ $Separator = ',';
+ }
+ # set statement
+ if ($Type eq 'where') {
+ $Statement = 'WHERE';
+ } elsif ($Type eq 'order') {
+ $Statement = 'ORDER BY';
+ } elsif ($Type eq 'having') {
+ $Statement = 'HAVING';
+ } else {
+ $Statement = 'GROUP BY';
+ }
+ # build query from expressions with separators
+ foreach my $Expression (@Expressions) {
+ if ($Expression) {
+ $SQLClause .= " $Separator " if ($SQLClause);
+ $SQLClause .= $Expression;
+ }
+ }
+ # add statement in front if not already present
+ $SQLClause = " $Statement " . $SQLClause
+ if ($SQLClause and $SQLClause !~ /$Statement/);
+ return $SQLClause;
+};
+
+
#####------------------------------- done ---------------------------------#####
1;
projects / usenet / newsstats.git / blobdiff