<div>
I believe the issue is the string concatenation. &nbsp;That returns a string not a date. 
 
You need to order by a date data type. 
 
Try: 
... 
&nbsp;row_number() over(partition by modelnumber order by to_date(deliverydate||deliverytime,'MM/DD/YYYYHH:MI:SS AM') desc) rn from 
... 
 
assuming the actual strings are in the same format shown in the Excel Spreadsheet.
</div>

<div>
slightwv, out of the box I was getting ORA-01849: hour must be between 1 and 12, I then went with &quot;to_timestamp&quot; but kept getting the same error.
</div>

<div>
The format mask has to match the data. 
 
Post an example of the actual data in the columns. &nbsp;Not in Excel. 
 
select &nbsp;deliverydate, deleverytime from deliveries where rownum&lt;6;
</div>

for_EE.jpg

<div>
Make the format mask look like the data. 
 
Given that data try: 
row_number() over(partition by modelnumber order by to_date(deliverydate||deliverytime,'YYYYMMDDHH24MISS') desc) rn from
</div>

<div>
If that still isn't right, you will need to come up with the mask that works for your data. 
 
Just about anything you can imagine is allowed. &nbsp;Here is the documentation that shows allowed values: 
<a href="https://docs.oracle.com/en/database/oracle/oracle-database/12.2/sqlrf/Format-Models.html#GUID-49B32A81-0904-433E-B7FE-51606672183A" rel="ugc">https://docs.oracle.com/en/database/oracle/oracle-database/12.2/sqlrf/Format-Models.html#GUID-49B32A81-0904-433E-B7FE-51606672183A</a>
</div>

<div>
Now its throwing me ORA-01850 hour must be between 0 and 23.
</div>

<div>
what is are the data types of deliverydate and deliverytime? 
 
your order by should depend on the data type and the concatenated string should be casted to a date type for the ordering to work. 
 
if Delievery date is a DATE column; you will have to do a TO_CHAR to convert it to a string at first. 
 
Assuming 
deliverydate is DATE type - apply TO_CHAR(deliverydate , 'YYYYMMDD') 
deliverytime is VARCHAR type - its format is HH:MI AM 
 
your order by can be - order by TO_DATE(TO_CHAR(deliverydate , 'YYYYMMDD')||deliverytime, 'YYYYMMDDHH:MI AM') desc
</div>

<div>
&gt;&gt; Now its throwing me ORA-01850 hour must be between 0 and 23. 
 
because your data is not in 24Hour format it is 12 hr format. YOu should use AM/PM mask HH:MI AM instead of HH24:MI
</div>

<div>
@Sujith, look at the actual sample data in <a href="#a42542756" rel="ugc">#a42542756</a> 
 
It looks like 24 hour clock. &nbsp;I believe the issue is with the second sample row that is missing the leading 0. &nbsp;The LPAD I posted should address that.
</div>

<div>
Slightwv, the posting ID: 42542773 solution worked, but I'm getting less data, something like 50 records less than what I know should be there, I'm doing some additional testing and will post my findings. 
 
Thx
</div>

<div>
From the data you posted in ID: 42542756, what would you expect as output?
</div>

<div>
I'm expecting to only pickup the very latest transaction based the date and time, the problem is when a modelnumber is switched hands in the same day, the current script is picking up the earlier transaction not the latest transaction.
</div>

<div>
We need sample data and the expected results. &nbsp;That way we can set up a test case and provide tested SQL that generates the exact results you provide.
</div>

<div>
The sample data is in an Excel spreadsheet, and here's the description of the table columns involved. 
1-Modelnumber Varchar(15) 
2-Releasenumber Varchar (6) 
3-Deliverydate number(8) 
4-Deliverytime number(6) 
5-Customer Varchar(15) 
<a href="https://filedb.experts-exchange.com/incoming/2018/04_w17/1304885/For_EE.xlsx" target="_blank" class="file-inline" title="DataSample (10 KB)"><svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512"><path d="M67.508 468.467c-58.005-58.013-58.016-151.92 0-209.943l225.011-225.04c44.643-44.645 117.279-44.645 161.92 0 44.743 44.749 44.753 117.186 0 161.944l-189.465 189.49c-31.41 31.413-82.518 31.412-113.926.001-31.479-31.482-31.49-82.453 0-113.944L311.51 110.491c4.687-4.687 12.286-4.687 16.972 0l16.967 16.971c4.685 4.686 4.685 12.283 0 16.969L184.983 304.917c-12.724 12.724-12.73 33.328 0 46.058 12.696 12.697 33.356 12.699 46.054-.001l189.465-189.489c25.987-25.989 25.994-68.06.001-94.056-25.931-25.934-68.119-25.932-94.049 0l-225.01 225.039c-39.249 39.252-39.258 102.795-.001 142.057 39.285 39.29 102.885 39.287 142.162-.028A739446.174 739446.174 0 0 1 439.497 238.49c4.686-4.687 12.282-4.684 16.969.004l16.967 16.971c4.685 4.686 4.689 12.279.004 16.965a755654.128 755654.128 0 0 0-195.881 195.996c-58.034 58.092-152.004 58.093-210.048.041z"/></svg>For_EE.xlsx</a>
</div>

For_EE.xlsx

<div>
As we have already pointed out: &nbsp;Excel doesn't work. &nbsp;It tries to guess at what the data is and converts it for you. 
 
We need raw data as it appears in the actual table. &nbsp;Make sure the same data you provide shows the problem you are having.
</div>

<div>
I don't want to know what you're expecting in words, but actual results from the query you want. I was really hoping to see something like this - 
 

<pre><code class="code-1 nolinks" id="code-20-42544191-1">ModelNumber Deliverydate Deliverytime
3661628 20040408 203000
3661751 20040410 094800
3661521 20040407 171800
2878598 20040407 145700
</code></pre>
 
With the explanation that ModelNumber 3661521 is returned with the delivery time of 171800 because the same ModelNumber and DeliveryDate was also returned but at a delivery time of 145300 which was earlier. 
 
If that's the case, then I think you just need to add the deliverydate to the row_number() partition in slightwv's solution - 
select modelnumber, deliverydate, delivery time from 
(select modelnumber, deliverydate, delivery time, 
&nbsp;row_number() over(partition by modelnumber, deliverydate order by to_date(deliverydate||lpad(deliverytime,6,'0'),'YYYYMMDDHH24MISS') desc) rn from deliveries) 
where rn = 1;
</div>

<div>
OK, I took a look at the attached spreadsheet and mocked up a test case. 
 
Here it is: 

<pre><code class="code-10 nolinks" id="code-20-42544300-1">/*
drop table tab1 purge;
create table tab1(
Modelnumber Varchar2(25),
Releasenumber Varchar2(10),
Deliverydate number(8),
Deliverytime number(6),
Customer Varchar2(15)
);

insert into tab1 values('AB-CA12W115918010925','E3087TKS11',20180401,13029,'Alpha');
insert into tab1 values('AB-CA13W115918080790','E0336TKS12',20180401,13032,'RAILEX');
insert into tab1 values('AB-CA14W115918021400','E2555TKS13',20180401,64953,'TRITON');
insert into tab1 values('AB-CA15W115918081536','E2555TKS14',20180401,64956,'MAXED');
insert into tab1 values('AB-CA16W115918021398','E2555TKS15',20180401,65000,'WILBURN');

insert into tab1 values('AB-CA17W115918081538','E2555TKS16',20180410,65006,'MADDOx');
insert into tab1 values('AB-CA17W115918081538','E2555TKS16',20180410,65011,'Alpha');

insert into tab1 values('AB-CA19W115918081537','E2555TKS18',20180410,65015,'RAILEX');
insert into tab1 values('AB-CA20W115918081535','E2555TKS19',20180410,65019,'TRITON');
insert into tab1 values('AB-CA20W115918081535','E2555TKS19',20180410,65021,'MAXED');
insert into tab1 values('AB-CA22W115918050925','E0226TKS21',20180410,65617,'WILBURN');
insert into tab1 values('AB-CA23W115918050930','E0226TKS22',20180410,65618,'MADDOx');
insert into tab1 values('AB-CA24W115918050931','E0226TKS23',20180410,65621,'Alpha');
insert into tab1 values('AB-CA24W115918050931','E0226TKS23',20180410,65624,'RAILEX');
insert into tab1 values('AB-CA24W115918050931','E0226TKS23',20180410,65627,'TRITON');
insert into tab1 values('AB-CA27W115918050934','E0226TKS26',20180410,65629,'MAXED');
insert into tab1 values('AB-CA28W115918050937','E0226TKS27',20180410,65632,'WILBURN');
insert into tab1 values('AB-CA28W115918050937','E0226TKS27',20180411,65635,'MADDOx');
insert into tab1 values('AB-CA30W115918021394','E0226TKS29',20180412,65638,'Alpha');
insert into tab1 values('AB-CA31W115918021395','E0226TKS30',20180413,65641,'RAILEX');
insert into tab1 values('AB-CA32W115918021397','E0226TKS31',20180414,65643,'TRITON');
insert into tab1 values('AB-CA33W115918021404','E0226TKS32',20180415,65646,'MAXED');
insert into tab1 values('AB-CA34W115918021405','E0226TKS33',20180416,65648,'WILBURN');
insert into tab1 values('AB-CA35W115918021410','E0226TKS34',20180417,65650,'MADDOx');
insert into tab1 values('AB-CA36W115918021411','E0226TKS35',20180418,65653,'Alpha');
insert into tab1 values('AB-CA37W115918081540','E0226TKS36',20180419,65656,'RAILEX');
insert into tab1 values('AB-CA38W115918021251','E0336TKS37',20180420,163441,'TRITON');
insert into tab1 values('AB-CA39W115918081303','E0336TKS38',20180421,163454,'MAXED');
insert into tab1 values('AB-CA40W115918200424','E0336TKS39',20180422,163512,'WILBURN');
insert into tab1 values('AB-CA41W115918021128','E0226TKS40',20180423,163521,'MADDOx');
commit;
*/
</code></pre>
 
Now I execute my SQL, here are the results: 

<pre><code class="code-10 nolinks" id="code-20-42544300-2">MODELNUMBER RELEASENUM DELIVERYDATE DELIVERYTIME CUSTOMER
------------------------- ---------- ------------ ------------ ---------------
AB-CA12W115918010925 E3087TKS11 20180401 13029 Alpha
AB-CA13W115918080790 E0336TKS12 20180401 13032 RAILEX
AB-CA14W115918021400 E2555TKS13 20180401 64953 TRITON
AB-CA15W115918081536 E2555TKS14 20180401 64956 MAXED
AB-CA16W115918021398 E2555TKS15 20180401 65000 WILBURN
AB-CA17W115918081538 E2555TKS16 20180410 65011 Alpha
AB-CA19W115918081537 E2555TKS18 20180410 65015 RAILEX
AB-CA20W115918081535 E2555TKS19 20180410 65021 MAXED
AB-CA22W115918050925 E0226TKS21 20180410 65617 WILBURN
AB-CA23W115918050930 E0226TKS22 20180410 65618 MADDOx
AB-CA24W115918050931 E0226TKS23 20180410 65627 TRITON
AB-CA27W115918050934 E0226TKS26 20180410 65629 MAXED
AB-CA28W115918050937 E0226TKS27 20180411 65635 MADDOx
AB-CA30W115918021394 E0226TKS29 20180412 65638 Alpha
AB-CA31W115918021395 E0226TKS30 20180413 65641 RAILEX
AB-CA32W115918021397 E0226TKS31 20180414 65643 TRITON
AB-CA33W115918021404 E0226TKS32 20180415 65646 MAXED
AB-CA34W115918021405 E0226TKS33 20180416 65648 WILBURN
AB-CA35W115918021410 E0226TKS34 20180417 65650 MADDOx
AB-CA36W115918021411 E0226TKS35 20180418 65653 Alpha
AB-CA37W115918081540 E0226TKS36 20180419 65656 RAILEX
AB-CA38W115918021251 E0336TKS37 20180420 163441 TRITON
AB-CA39W115918081303 E0336TKS38 20180421 163454 MAXED
AB-CA40W115918200424 E0336TKS39 20180422 163512 WILBURN
AB-CA41W115918021128 E0226TKS40 20180423 163521 MADDOx

25 rows selected.
</code></pre>
 
 
Using awking00's suggestion, here are the results: 

<pre><code class="code-10 nolinks" id="code-20-42544300-3">MODELNUMBER RELEASENUM DELIVERYDATE DELIVERYTIME CUSTOMER
------------------------- ---------- ------------ ------------ ---------------
AB-CA12W115918010925 E3087TKS11 20180401 13029 Alpha
AB-CA13W115918080790 E0336TKS12 20180401 13032 RAILEX
AB-CA14W115918021400 E2555TKS13 20180401 64953 TRITON
AB-CA15W115918081536 E2555TKS14 20180401 64956 MAXED
AB-CA16W115918021398 E2555TKS15 20180401 65000 WILBURN
AB-CA17W115918081538 E2555TKS16 20180410 65011 Alpha
AB-CA19W115918081537 E2555TKS18 20180410 65015 RAILEX
AB-CA20W115918081535 E2555TKS19 20180410 65021 MAXED
AB-CA22W115918050925 E0226TKS21 20180410 65617 WILBURN
AB-CA23W115918050930 E0226TKS22 20180410 65618 MADDOx
AB-CA24W115918050931 E0226TKS23 20180410 65627 TRITON
AB-CA27W115918050934 E0226TKS26 20180410 65629 MAXED
AB-CA28W115918050937 E0226TKS27 20180410 65632 WILBURN
AB-CA28W115918050937 E0226TKS27 20180411 65635 MADDOx
AB-CA30W115918021394 E0226TKS29 20180412 65638 Alpha
AB-CA31W115918021395 E0226TKS30 20180413 65641 RAILEX
AB-CA32W115918021397 E0226TKS31 20180414 65643 TRITON
AB-CA33W115918021404 E0226TKS32 20180415 65646 MAXED
AB-CA34W115918021405 E0226TKS33 20180416 65648 WILBURN
AB-CA35W115918021410 E0226TKS34 20180417 65650 MADDOx
AB-CA36W115918021411 E0226TKS35 20180418 65653 Alpha
AB-CA37W115918081540 E0226TKS36 20180419 65656 RAILEX
AB-CA38W115918021251 E0336TKS37 20180420 163441 TRITON
AB-CA39W115918081303 E0336TKS38 20180421 163454 MAXED
AB-CA40W115918200424 E0336TKS39 20180422 163512 WILBURN
AB-CA41W115918021128 E0226TKS40 20180423 163521 MADDOx

26 rows selected.
</code></pre>
 
His added an extra row. &nbsp;Is that the correct results from the sample data provided?
</div>

<div>
The posted output of both extracts are right on the money, it's exactly what I'm hoping for, but so far not getting although I executed the script as called for in ID:42544191 by awking00, with that in mind, I'm starting to believe what Slightwv said in ID:42542934, we'll see, I'm looking at other ways of accomplishing this. 
Thx
</div>

<div>
&gt;&gt;I'm looking at other ways of accomplishing this. 
 
No need to look. &nbsp;You know what data is missing from your result set. 
 
Add examples to the test case I provided then provide expected results. &nbsp;We can probably handle it from there.
</div>

<div>
If you think there might be a data problem, then post the actual data (it doesn't appear to be proprietary) and indicate which records should not appear (or only the records that should appear) in the query results. Please don't post the data as a picture, either in text format or an excel spreadsheet will do.
</div>

<div>
&gt;&gt;or an excel spreadsheet will do. 
 
I prefer a TXT file. &nbsp;As seen above: &nbsp;Excel can &quot;change&quot; the data.
</div>

<div>
Enclosed is a tab-separated txt file, hope this will help, to bring the point home, look at Modelnumber AB-CA17W115918081538 with Deliverydate of 20180410 &amp;&nbsp;Deliverytime of 5006 to MADDOX &amp;&nbsp;5011 to Aplha, the query is still picking up the earlier transaction (MADDOX).<a href="https://filedb.experts-exchange.com/incoming/2018/04_w17/1305476/For_EE.txt" target="_blank" class="file-inline" title="OutputToText (1 KB)"><svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512"><path d="M67.508 468.467c-58.005-58.013-58.016-151.92 0-209.943l225.011-225.04c44.643-44.645 117.279-44.645 161.92 0 44.743 44.749 44.753 117.186 0 161.944l-189.465 189.49c-31.41 31.413-82.518 31.412-113.926.001-31.479-31.482-31.49-82.453 0-113.944L311.51 110.491c4.687-4.687 12.286-4.687 16.972 0l16.967 16.971c4.685 4.686 4.685 12.283 0 16.969L184.983 304.917c-12.724 12.724-12.73 33.328 0 46.058 12.696 12.697 33.356 12.699 46.054-.001l189.465-189.489c25.987-25.989 25.994-68.06.001-94.056-25.931-25.934-68.119-25.932-94.049 0l-225.01 225.039c-39.249 39.252-39.258 102.795-.001 142.057 39.285 39.29 102.885 39.287 142.162-.028A739446.174 739446.174 0 0 1 439.497 238.49c4.686-4.687 12.282-4.684 16.969.004l16.967 16.971c4.685 4.686 4.689 12.279.004 16.965a755654.128 755654.128 0 0 0-195.881 195.996c-58.034 58.092-152.004 58.093-210.048.041z"/></svg>For_EE.txt</a>
</div>

For_EE.txt

<div>
If you look at the results I posted from my test runs, both show: 
CA17W115918081538 &nbsp; &nbsp; &nbsp;E2555TKS16 &nbsp; &nbsp; 20180410 &nbsp; &nbsp; &nbsp; &nbsp;65011 Alpha 
 
Maybe something else you are adding to your query is preventing that row from coming back?
</div>

<div>
Here it is including all of the fields - 
 
SQL&gt; select * from deliveries; 
 
MODELNUMBER &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;RELEASENUMBER &nbsp; &nbsp; &nbsp; &nbsp;DELIVERY DELIVE CUSTOMER 
-------------------- -------------------- -------- ------ ---------- 
AB-CA12W115918010925 E3087TKS11 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180401 13029 &nbsp;Alpha 
AB-CA13W115918080790 E0336TKS12 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180401 13032 &nbsp;RAILEX 
AB-CA14W115918021400 E2555TKS13 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180401 64953 &nbsp;TRITON 
AB-CA15W115918081536 E2555TKS14 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180401 64956 &nbsp;MAXED 
AB-CA16W115918021398 E2555TKS15 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180401 65000 &nbsp;WILBURN 
AB-CA17W115918081538 E2555TKS16 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180410 65006 &nbsp;MADDOx 
AB-CA17W115918081538 E2555TKS16 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180410 65011 &nbsp;Alpha 
AB-CA19W115918081537 E2555TKS18 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180410 65015 &nbsp;RAILEX 
AB-CA20W115918081535 E2555TKS19 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180410 65019 &nbsp;TRITON 
AB-CA20W115918081535 E2555TKS19 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180410 65021 &nbsp;MAXED 
AB-CA22W115918050925 E0226TKS21 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180410 65617 &nbsp;WILBURN 
AB-CA23W115918050930 E0226TKS22 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180410 65618 &nbsp;MADDOx 
AB-CA24W115918050931 E0226TKS23 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180410 65621 &nbsp;Alpha 
AB-CA24W115918050931 E0226TKS23 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180410 65624 &nbsp;RAILEX 
AB-CA24W115918050931 E0226TKS23 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180410 65627 &nbsp;TRITON 
AB-CA27W115918050934 E0226TKS26 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180410 65629 &nbsp;MAXED 
AB-CA28W115918050937 E0226TKS27 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180410 65632 &nbsp;WILBURN 
AB-CA28W115918050937 E0226TKS27 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180411 65635 &nbsp;MADDOx 
AB-CA30W115918021394 E0226TKS29 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180412 65638 &nbsp;Alpha 
AB-CA31W115918021395 E0226TKS30 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180413 65641 &nbsp;RAILEX 
AB-CA32W115918021397 E0226TKS31 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180414 65643 &nbsp;TRITON 
AB-CA33W115918021404 E0226TKS32 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180415 65646 &nbsp;MAXED 
AB-CA34W115918021405 E0226TKS33 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180416 65648 &nbsp;WILBURN 
AB-CA35W115918021410 E0226TKS34 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180417 65650 &nbsp;MADDOx 
AB-CA36W115918021411 E0226TKS35 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180418 65653 &nbsp;Alpha 
AB-CA37W115918081540 E0226TKS36 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180419 65656 &nbsp;RAILEX 
AB-CA38W115918021251 E0336TKS37 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180420 163441 TRITON 
AB-CA39W115918081303 E0336TKS38 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180421 163454 MAXED 
AB-CA40W115918200424 E0336TKS39 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180422 163512 WILBURN 
AB-CA41W115918021128 E0226TKS40 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180423 163521 Maddox 
 
SQL&gt; select modelnumber, releasenumber, deliverydate, deliverytime, customer from 
&nbsp; 2 &nbsp; (select modelnumber, deliverydate, releasenumber, deliverytime, customer, 
&nbsp; 3 &nbsp; &nbsp;row_number() over(partition by modelnumber, deliverydate order by to_date(deliverydate||lpad(deliverytime,6,'0'), 
'YYYYMMDDHH24MISS') desc) rn from deliveries) 
&nbsp; 4 &nbsp; where rn = 1; 
 
MODELNUMBER &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;RELEASENUMBER &nbsp; &nbsp; &nbsp; &nbsp;DELIVERY DELIVE CUSTOMER 
-------------------- -------------------- -------- ------ ---------- 
AB-CA12W115918010925 E3087TKS11 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180401 13029 &nbsp;Alpha 
AB-CA13W115918080790 E0336TKS12 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180401 13032 &nbsp;RAILEX 
AB-CA14W115918021400 E2555TKS13 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180401 64953 &nbsp;TRITON 
AB-CA15W115918081536 E2555TKS14 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180401 64956 &nbsp;MAXED 
AB-CA16W115918021398 E2555TKS15 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180401 65000 &nbsp;WILBURN 
AB-CA17W115918081538 E2555TKS16 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180410 65011 &nbsp;Alpha 
AB-CA19W115918081537 E2555TKS18 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180410 65015 &nbsp;RAILEX 
AB-CA20W115918081535 E2555TKS19 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180410 65021 &nbsp;MAXED 
AB-CA22W115918050925 E0226TKS21 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180410 65617 &nbsp;WILBURN 
AB-CA23W115918050930 E0226TKS22 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180410 65618 &nbsp;MADDOx 
AB-CA24W115918050931 E0226TKS23 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180410 65627 &nbsp;TRITON 
AB-CA27W115918050934 E0226TKS26 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180410 65629 &nbsp;MAXED 
AB-CA28W115918050937 E0226TKS27 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180410 65632 &nbsp;WILBURN 
AB-CA28W115918050937 E0226TKS27 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180411 65635 &nbsp;MADDOx 
AB-CA30W115918021394 E0226TKS29 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180412 65638 &nbsp;Alpha 
AB-CA31W115918021395 E0226TKS30 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180413 65641 &nbsp;RAILEX 
AB-CA32W115918021397 E0226TKS31 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180414 65643 &nbsp;TRITON 
AB-CA33W115918021404 E0226TKS32 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180415 65646 &nbsp;MAXED 
AB-CA34W115918021405 E0226TKS33 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180416 65648 &nbsp;WILBURN 
AB-CA35W115918021410 E0226TKS34 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180417 65650 &nbsp;MADDOx 
AB-CA36W115918021411 E0226TKS35 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180418 65653 &nbsp;Alpha 
AB-CA37W115918081540 E0226TKS36 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180419 65656 &nbsp;RAILEX 
AB-CA38W115918021251 E0336TKS37 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180420 163441 TRITON 
AB-CA39W115918081303 E0336TKS38 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180421 163454 MAXED 
AB-CA40W115918200424 E0336TKS39 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180422 163512 WILBURN 
AB-CA41W115918021128 E0226TKS40 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 20180423 163521 Maddox
</div>

<div>
Ran the script against another database and all came out fine.
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<div class="content wysiwyg-content">
I've got the query below against the table attached, I'm still getting mixed results as to the customer that has the product although I'm picking on the first instance of the transaction, the problem is only on days when the Model has exchanged hands on the same day. &nbsp; &nbsp; 
 
select 
&nbsp; &nbsp; modelnumber, 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;releasenumber, 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;deliverydate, 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;deliverytime, 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;customer 
&nbsp; &nbsp; from 
&nbsp; &nbsp; (select 
&nbsp; &nbsp; modelnumber, 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;releasenumber, 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;deliverydate, 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;deliverytime, 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;customer, 
&nbsp; &nbsp; row_number() over(partition by modelnumber order by deliverydate||deliverytime desc) rn from 
&nbsp; &nbsp; deliveries) 
&nbsp; &nbsp; where rn=1 And 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;etc......
</div>
</div>

I've got the query below against the table attached, I'm still getting mixed results as to the customer that has the product although I'm picking on the first instance of the transaction, the problem is only on days when the Model has exchanged hands on the same day.     

select
    modelnumber,
	releasenumber,
	deliverydate,
	deliverytime,
	customer
    from
    (select
    modelnumber,
	releasenumber,
	deliverydate,
	deliverytime,
	customer,
    row_number() over(partition by modelnumber order by deliverydate||deliverytime desc) rn from
    deliveries)
    where rn=1 And
	etc......

The row_number in the subselect of an Oracle SQL Query is not picking the exact record.

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