Currently within the program I am working on I have to compare tables in a database. To do this I intend to use an SQL outer join. My problem is that I will have no idea how many tables I will have to select from or how many columns are to be retrieved.
I intend to create the SQL statment dynamically. Store it as a scalar and then run it. What I have left to do, which is causing me a little trouble, is the second half of the statement.
What may make it easier to understand if you are not a SQL person is what I need to do is create a string made up from values stored within arrays/hashes.
Below are a few examples of what I will have and what I need to create. The resulting code however has to work for any amount of arrays or values.

input:
%hash = ( "view0" => "buffersize, size, value",
          "view1" => "buffersize, size, value");
output:
view0 full outer join view1 on view0.size = view1.size and view0.buffe
+rsize = view1.buffersize

[download]
please notice that the last value in each hash element is not included in the result 
input:
%hash = ( "view0" => "buffersize, size, value",
          "view1" => "buffersize, size, value",
          "view2" => "buffersize, size, value");
output:
view0 full outer join view1 on view0.size = view1.size and view0.buffe
+rsize = view1.buffersize full outer join view2 on view1.size = view2.
+size and view1.buffersize = view2.buffersize

[download]
again the last element value in each hash element is omitted 
input:
%hash = ( "view0" => "buffersize, size, value",
          "view1" => "buffersize, size, value",
          "view2" => "buffersize, size, value"
          "view3" => "buffersize, size, value");
output:
view0 full outer join view1 on view0.size = view1.size and view0.buffe
+rsize = view1.buffersize full outer join view2 on view1.size = view2.
+size and view1.buffersize = view2.buffersize full outer join view3 on
+ view2.size = view3.size and view2.buffersize = view3.buffersize

[download]
Thanks. And if anything is unclear please ask. It does take a while to wrap your head around what is needed.

j o h n i r l .

Sum day soon I'Il lern how 2 spelI (nad tYpe)

In reply to Using hash elements to create a string by johnirl

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