match variable name in reading each line of a file to create view ddl - perl

Question

I have an input file,
TableName1.Column1
TableName1.Column2
TableName2.Column1
TableName2.Column2
TableName3.Column3 etc
I would like it read each of the line and distinguish what columns belong for TableName1 so I can build a view ddl like this: CREATE VIEW TABLENAME1 AS SELECT Column1, Column2 From TableName1; and Next will be View TableName2 etc.
my $file = "summary.csv";
open (my $FH, '<', $file) or die "Can't open '$file' for read: $!";
my #lines;
while (my $line = <$FH>) {
push (#lines, $line);
}
close $FH or die "Cannot close $file: $!";
my $ln=#lines;
for (my $x=0; $x<$ln; $x++){
print("---Start->\n") if($x == 0);
print "---------------->\n";
my $first = (split /\./, $lines[$x] )[0];
my $second = $first;
print "Second is: $second \n";
if ((split /\./, $lines[$x] )[0] eq $first )
{
print "Same Table: $lines[$x]";
}
else
{
print "Next Table: $lines[$x]";
}
print("---End-->\n") if($x == $ln -1);
}

Answer 1

I'd do it something like this.
Parse the data into a data structure. I'm using an array of anonymous arrays. In the anonymous arrays, the first element is the table name and any other elements are columns.
#!/usr/bin/perl
use strict;
use warnings;
use feature 'say';
my #tables;
my $curr_table = '';
# Note: I used a DATA filehandle to test this. You'll need to
# insert your file-opening code here.
while (<DATA>) {
chomp;
my ($table, $column) = split /\./;
if ($table ne $curr_table) {
push #tables, [ $table ];
$curr_table = $table;
}
push #{ $tables[-1] }, $column;
}
And then walk the data structure to do whatever you want with the data (here, I'm just displaying it).
for my $t (#tables) {
my ($table, #columns) = #{ $t };
say "Table: table";
say " * $_" for #columns;
}