Number of elements in array

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Hi Monks,


      while(my @row_A_count_A_Ref_vs_Comp_B = $sth_Count_Ref_vs_Comp_B
+->fetchrow_array()) {
[download]

I really want to know what the number of elements in @row_A_count_A_Ref_vs_Comp_B is. I have tried the obvious, however I get strange numbers back. I think the problems lie in how the array is filled. Suggestion for lines on investigation welcomed.

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Re: Number of elements in array by blue_cowdawg (Monsignor) on Sep 24, 2012 at 13:57 UTC
Suggestion for lines on investigation welcomed OH Chilly Monk, If I want to know the number of elements in an array I'd try one of two things: `# assume two arrays with a number of elements # @rray1 & @rray2 my $elements_1 = scalar @rray1; # or my $elements_2 = $#rray2 + 1;` [download] Either of the two will work. Peter L. Berghold -- Unix Professional Peter -at- Berghold -dot- Net; AOL IM redcowdawg Yahoo IM: blue_cowdawg	[reply] [d/l]
Re: Number of elements in array by Corion (Patriarch) on Sep 24, 2012 at 13:48 UTC
What is "the obvious", and what strange numbers did you get?	[reply]
Re: Number of elements in array by NetWallah (Canon) on Sep 24, 2012 at 13:55 UTC
If you want to get the number of rows in a database table, the most efficient way would be to let the database count them: `...prepare ("Select COUNT(*) FROM TABLE_OR_QUERY"); # TABLE_OR_QUERY can be another (SELECT...) statement` [download] Most databases will optimize queries, so you can do the count query, then do the data query as 2 separate queries. I hope life isn't a big joke, because I don't get it. -SNL	[reply] [d/l]
Re^2: Number of elements in array by tobyink (Canon) on Sep 24, 2012 at 14:03 UTC
This counts the number of rows. The OP was counting the number of columns. Of course, it's possible that the OP did actually want the number of rows... `perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'`	[reply]
Re: Number of elements in array by Anonymous Monk on Sep 24, 2012 at 13:43 UTC
I have tried the obvious, however I get strange numbers back. Such as? Suggestion for lines on investigation welcomed. trace, Dumper, the basics :)	[reply]


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