Showing a cumlative total by month

<div dir="ltr">Good morning all,<br /><br />We have a system that maintains information about files that have been
uploadedto our system. I have a view that shows for each month the total size of all files submitted tht month. I would
liketo add a running total column to the view, but can't quite get there. I figured out how to show the information I
wantusing a CTE, but I can not figure out how to translate that to a single query to define a view with. So I'm hoping
someonecan point me in the right direction.<br /><br />SELECT VERSION();<br />                            version      
                                            <br
/>----------------------------------------------------------------------------------------------------------------<br
/> PostgreSQL9.1.18 on x86_64-unknown-linux-gnu, compiled by gcc (GCC) 4.4.7 20120313 (Red Hat 4.4.7-11), 64-bit<br
/><br/>DROP TABLE uploaded_files;<br /><br />CREATE TABLE uploaded_files<br />(<br />   file_id              SERIAL    
                  NOT NULL,<br />   upload_date          TIMESTAMP WITH TIME ZONE      NOT NULL,<br />   upload_size  
      BIGINT                        NOT NULL,<br />   PRIMARY KEY (file_id)<br />);<br /><br />This test case is
populatedwith a handful of random records (659), and the following CTE seems to extract the information I am after
(stillnot positive I have the date down exactly, but I can deal with that):<br /><br />WITH upload_summary AS<br />(<br
/>  SELECT EXTRACT(YEAR FROM upload_date) AS up_year,<br />          LPAD(CAST(EXTRACT(MONTH FROM upload_date) AS
TEXT),2, '0') AS up_month,<br />          SUM(upload_size) AS monthly_total<br />   FROM uploaded_files<br />   GROUP
BYup_month, up_year<br />)<br />SELECT u.up_year,<br />       u.up_month,<br />       u.monthly_total,<br />     
 (SELECTSUM(monthly_total)<br />        FROM upload_summary<br />        WHERE CAST(CONCAT(up_year,<br />             
           '-',<br />                          up_month,<br />                          '-01 00:00:00-05')<br />       
          AS TIMESTAMP) <=<br />              CAST(CONCAT(u.up_year,<br />                          '-',<br />     
                   u.up_month,<br />                          '-01 00:00:00-05')<br />                   AS
TIMESTAMP)<br/>       ) AS cumulative<br />FROM upload_summary u<br />ORDER BY up_year, up_month;<br /><br /> up_year |
up_month| monthly_total  |   cumulative  <br />---------+----------+----------------+----------------<br />    2014 |
01      |     3179135699 |     3179135699<br />    2014 | 02       |     1634499060 |     4813634759<br />    2014 | 03
     |     4278982588 |     9092617347<br />    2014 | 04       |   142238544857 |   151331162204<br />    2014 | 05  
   |   357240707209 |   508571869413<br />    2014 | 06       |    64339859968 |   572911729381<br />    2014 | 07    
 |    25513017728 |   598424747109<br />    2014 | 08       |    11020669492 |   609445416601<br />    2014 | 09      
|    1018774598 |   610464191199<br />    2014 | 10       |    76752535951 |   687216727150<br />    2014 | 11       |
   4611404964 |   691828132114<br />    2014 | 12       |    69607199452 |   761435331566<br />    2015 | 01       |  
   15700525 |   761451032091<br />    2015 | 02       |    34234715981 |   795685748072<br />    2015 | 03       |
 1484150449194|  2279836197266<br />    2015 | 04       | 13096208914706 | 15376045111972<br />    2015 | 05       |  
  814385166 | 15376859497138<br />    2015 | 06       |      563829413 | 15377423326551<br />    2015 | 07       |    
 656007272| 15378079333823<br />    2015 | 08       |  1828956674258 | 17207036008081<br />    2015 | 09       |    
 822601322| 17207858609403<br /><br /><br /><br />The basic view definition gives the first three columns (date fields
concatenatedinto one):<br />SELECT CONCAT(EXTRACT(YEAR FROM upload_date),<br />              '-',<br />             
LPAD(CAST(EXTRACT(MONTHFROM upload_date) AS TEXT), 2, '0')) AS mon,<br />       SUM(upload_size) AS monthly_total<br
/>FROMuploaded_files u<br />GROUP BY EXTRACT(MONTH FROM upload_date), EXTRACT(YEAR FROM upload_date)<br />ORDER BY
EXTRACT(YEARFROM upload_date), EXTRACT(MONTH FROM upload_date);<br /><br />   mon   | monthly_total<br
/>---------+----------------<br/> 2014-01 |     3179135699<br /> 2014-02 |     1634499060<br /> 2014-03 |    
4278982588<br/> 2014-04 |   142238544857<br /> 2014-05 |   357240707209<br /> 2014-06 |    64339859968<br /> 2014-07 |
  25513017728<br /> 2014-08 |    11020669492<br /> 2014-09 |     1018774598<br /> 2014-10 |    76752535951<br
/> 2014-11|     4611404964<br /> 2014-12 |    69607199452<br /> 2015-01 |       15700525<br /> 2015-02 |  
 34234715981<br/> 2015-03 |  1484150449194<br /> 2015-04 | 13096208914706<br /> 2015-05 |      814385166<br /> 2015-06
|     563829413<br /> 2015-07 |      656007272<br /> 2015-08 |  1828956674258<br /> 2015-09 |      822601322<br /><br
/><br/>I just can't figure out how to specify the summation of the file sizes through each month in a static query. Any
suggestions?<br/><br />Thanks,<br />David</div>