newsstats/NewsStats.pm

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# NewsStats.pm
#
# Library functions for the NewsStats package.
#
# 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.
package NewsStats;
use strict;
use warnings;
our ($VERSION, @ISA, @EXPORT, @EXPORT_OK, %EXPORT_TAGS);
require Exporter;
@ISA = qw(Exporter);
@EXPORT = qw(
$MyVersion
$PackageVersion
$FullPath
$HomePath
ShowVersion
ShowPOD
ReadConfig
OverrideConfig
InitDB
Bleat
);
@EXPORT_OK = qw(
GetTimePeriod
LastMonth
SplitPeriod
ListMonth
ListNewsgroups
ParseHierarchies
ReadGroupList
OutputData
FormatOutput
SQLHierarchies
SQLSortOrder
SQLGroupList
SQLSetBounds
SQLBuildClause
GetMaxLength
);
%EXPORT_TAGS = ( TimePeriods => [qw(GetTimePeriod LastMonth SplitPeriod
ListMonth)],
Output => [qw(OutputData FormatOutput)],
SQLHelper => [qw(SQLHierarchies SQLSortOrder SQLGroupList
SQLSetBounds SQLBuildClause GetMaxLength)]);
$VERSION = '0.01';
our $PackageVersion = '0.01';
use Data::Dumper;
use File::Basename;
use Config::Auto;
use DBI;
#####-------------------------------- Vars --------------------------------#####
# trim the path
our $FullPath = $0;
our $HomePath = dirname($0);
$0 =~ s%.*/%%;
# set version string
our $MyVersion = "$0 $::VERSION (NewsStats.pm $VERSION)";
#####------------------------------- Basics -------------------------------#####
################################################################################
################################################################################
sub ShowVersion {
################################################################################
### display version and exit
print "NewsStats v$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', $FullPath);
exit(100);
};
################################################################################
################################################################################
sub ReadConfig {
################################################################################
### read config via Config::Auto
### IN : $ConfFile: config filename
### OUT: reference to a hash containing the configuration
my ($ConfFile) = @_;
return Config::Auto::parse($ConfFile, format => 'equal');
};
################################################################################
################################################################################
sub OverrideConfig {
################################################################################
### override configuration values
### IN : $ConfigR : reference to configuration hash
### $OverrideR: reference to a hash containing overrides
my ($ConfigR,$OverrideR) = @_;
my %Override = %$OverrideR;
# Config hash empty?
&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) {
$$ConfigR{$Key} = $Override{$Key};
};
};
################################################################################
################################################################################
sub InitDB {
################################################################################
### initialise database connection
### IN : $ConfigR: reference to configuration hash
### $Die : if TRUE, die if connection fails
### OUT: DBHandle
my ($ConfigR,$Die) = @_;
my %Conf = %$ConfigR;
my $DBHandle = DBI->connect(sprintf('DBI:%s:database=%s;host=%s',
$Conf{'DBDriver'},$Conf{'DBDatabase'},
$Conf{'DBHost'}), $Conf{'DBUser'},
$Conf{'DBPw'}, { PrintError => 0 });
if (!$DBHandle) {
&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 ------------------------------#####
################################################################################
sub ListNewsgroups {
################################################################################
### explode a (scalar) list of newsgroup names to a list of newsgroup and
### hierarchy names where every newsgroup and hierarchy appears only once:
### de.alt.test,de.alt.admin -> de.ALL, de.alt.ALL, de.alt.test, de.alt.admin
### IN : $Newsgroups : a list of newsgroups (content of Newsgroups: header)
### $TLH : top level hierarchy (all other newsgroups are ignored)
### $ValidGroupsR: reference to a hash containing all valid newsgroups
### as keys
### OUT: %Newsgroups : hash containing all newsgroup and hierarchy names as keys
my ($Newsgroups,$TLH,$ValidGroupsR) = @_;
my %ValidGroups = %{$ValidGroupsR} if $ValidGroupsR;
my %Newsgroups;
chomp($Newsgroups);
# remove whitespace from contents of Newsgroups:
$Newsgroups =~ s/\s//;
# call &HierarchyCount for each newsgroup in $Newsgroups:
for (split /,/, $Newsgroups) {
# don't count newsgroup/hierarchy in wrong TLH
next if($TLH and !/^$TLH/);
# don't count invalid newsgroups
if(%ValidGroups and !defined($ValidGroups{$_})) {
warn (sprintf("DROPPED: %s\n",$_));
next;
}
# add original newsgroup to %Newsgroups
$Newsgroups{$_} = 1;
# add all hierarchy elements to %Newsgroups, amended by '.ALL',
# i.e. de.alt.ALL and de.ALL
foreach (ParseHierarchies($_)) {
$Newsgroups{$_.'.ALL'} = 1;
}
};
return %Newsgroups;
};
################################################################################
sub ParseHierarchies {
################################################################################
### return a list of all hierarchy levels a newsgroup belongs to
### (for de.alt.test.moderated that would be de/de.alt/de.alt.test)
### IN : $Newsgroup : a newsgroup name
### OUT: @Hierarchies: array containing all hierarchies the newsgroup belongs to
my ($Newsgroup) = @_;
my @Hierarchies;
# strip trailing dots
$Newsgroup =~ s/(.+)\.+$/$1/;
# butcher newsgroup name by "." and add each hierarchy to @Hierarchies
# i.e. de.alt.test: "de.alt" and "de"
while ($Newsgroup =~ /\./) {
$Newsgroup =~ s/^((?:\.?[^.]+)*)\.[^.]+$/$1/;
push @Hierarchies, $Newsgroup;
};
return @Hierarchies;
};
################################################################################
sub ReadGroupList {
################################################################################
### read a list of valid newsgroups from file (each group on one line,
### ignoring everything after the first whitespace and so accepting files
### in checkgroups format as well as (parts of) an INN active file)
### IN : $Filename : file to read
### OUT: \%ValidGroups: hash containing all valid newsgroups
my ($Filename) = @_;
my %ValidGroups;
open (my $LIST,"<$Filename") or &Bleat(2,"Cannot read $Filename: $!");
while (<$LIST>) {
s/^\s*(\S+).*$/$1/;
chomp;
next if /^$/;
$ValidGroups{$_} = '1';
};
close $LIST;
return \%ValidGroups;
};
################################################################################
#####----------------------------- TimePeriods ----------------------------#####
################################################################################
sub GetTimePeriod {
################################################################################
### 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';
$SQL = '';
} else {
# invalid input
return (undef,undef);
}
return ($Verbal,$SQL);
};
################################################################################
sub LastMonth {
################################################################################
### get last month from todays date in YYYY-MM format
### OUT: last month as YYYY-MM
# get today's date
my (undef,undef,undef,undef,$Month,$Year,undef,undef,undef) = localtime(time);
# $Month is already defined from 0 to 11, so no need to decrease it by 1
$Year += 1900;
if ($Month < 1) {
$Month = 12;
$Year--;
};
# return last month
return sprintf('%4d-%02d',$Year,$Month);
};
################################################################################
sub CheckMonth {
################################################################################
### 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;
};
################################################################################
sub SplitPeriod {
################################################################################
### split a time period denoted by YYYY-MM:YYYY-MM into start and end month
### IN : $Period: time period
### OUT: $StartMonth, $EndMonth
my ($Period) = @_;
my ($StartMonth, $EndMonth) = split /:/, $Period;
($StartMonth,$EndMonth) = CheckMonth($StartMonth,$EndMonth);
# switch parameters as necessary
if ($EndMonth gt $StartMonth) {
return ($StartMonth, $EndMonth);
} else {
return ($EndMonth, $StartMonth);
};
};
################################################################################
sub ListMonth {
################################################################################
### return a list of months (YYYY-MM) between start and end month
### 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 /-/, $StartMonth;
# define @Months
my (@Months);
until ("$Year-$Month" gt $EndMonth) {
push @Months, "$Year-$Month";
$Month = "$Month"; # force string context
$Month++;
if ($Month > 12) {
$Month = '01';
$Year++;
};
};
return @Months;
};
#####---------------------------- OutputFormats ---------------------------#####
################################################################################
sub OutputData {
################################################################################
### read database query results from DBHandle and print results with formatting
### 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
### $PadGroup : padding length for key field (optional) for 'pretty'
my ($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 = $Month;
}
# set output file handle
if (!$FileTempl) {
$Handle = *STDOUT{IO}; # set $Handle to a reference to STDOUT
} elsif (!defined($LastIteration) or $LastIteration ne $Caption) {
close $OUT if ($LastIteration);
# 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, $Comments, $Caption, $Key, $Value,
$Precision, $PadGroup);
$LastIteration = $Caption;
};
close $OUT if ($FileTempl);
};
################################################################################
sub FormatOutput {
################################################################################
### format information for output according to format specifier
### 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, $Comments, $Caption, $Key, $Value, $Precision, $PadGroup) = @_;
my ($Output);
# keep last caption in mind
our ($LastIteration);
# create one line of output
if ($Format eq 'dump') {
# 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 (caption key value)
$Output = sprintf ("%s %s %u\n",$Caption,$Key,$Value);
} elsif ($Format eq 'pretty') {
# 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;
};
#####------------------------- QueryModifications -------------------------#####
################################################################################
sub SQLHierarchies {
################################################################################
### add exclusion of hierarchy levels (de.alt.ALL) from SQL query by
### amending the WHERE clause if $ShowHierarchies is false (or don't, if it is
### true, accordingly)
### IN : $ShowHierarchies: boolean value
### OUT: SQL code
my ($ShowHierarchies) = @_;
return $ShowHierarchies ? '' : "newsgroup NOT LIKE '%.ALL'";
};
################################################################################
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
### $HavingClause: HAVING clause
### @BindVars : bind variables for WHERE clause
### OUT: $Length: length of longest instnace of $Field
my ($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' expression
### IN : $Newsgroups: list of newsgroups (group.one.*:group.two:group.three.*)
### OUT: SQL code to become part of a 'WHERE' clause,
### list of newsgroups for SQL bindings
my ($Newsgroups) = @_;
# substitute '*' wildcard with SQL wildcard character '%'
$Newsgroups =~ s/\*/%/g;
# just one newsgroup?
return (SQLGroupWildcard($Newsgroups),$Newsgroups) if $Newsgroups !~ /:/;
my ($SQL,@WildcardGroups,@NoWildcardGroups);
# list of newsgroups separated by ':'
my @GroupList = split /:/, $Newsgroups;
foreach (@GroupList) {
if ($_ !~ /%/) {
# add to list of newsgroup names WITHOUT wildcard
push (@NoWildcardGroups,$_);
} else {
# add to list of newsgroup names WITH wildcard
push (@WildcardGroups,$_);
# add wildcard to SQL clause
# 'OR' if SQL clause is not empty
$SQL .= ' OR ' if $SQL;
$SQL .= 'newsgroup LIKE ?'
}
};
if (scalar(@NoWildcardGroups)) {
# add 'OR' if SQL clause is not empty
$SQL .= ' OR ' if $SQL;
if (scalar(@NoWildcardGroups) < 2) {
# special case: just one newsgroup without wildcard
$SQL .= 'newsgroup = ?';
} else {
# create list of newsgroups to include: 'newsgroup IN (...)'
$SQL .= 'newsgroup IN (';
my $SQLin;
foreach (@NoWildcardGroups) {
$SQLin .= ',' if $SQLin;
$SQLin .= '?';
}
# add list to SQL clause
$SQL .= $SQLin .= ')';
}
}
# add brackets '()' to SQL clause as needed (more than one wildcard group)
if (scalar(@WildcardGroups)) {
$SQL = '(' . $SQL .')';
}
# rebuild @GroupList in (now) correct order
@GroupList = (@WildcardGroups,@NoWildcardGroups);
return ($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;