These SQL clauses are equivalent?

Hi, previously I was working in a SQL statement that returns potentially 1 million rows. The 'order by' clause contributes significantly the cost when I checked its plan to explain.

select ...
from ...
order by field1, field2, field3;

Then I found another way to make the order of who has much lower costs to explain the plan.

select ...
, dense_rank() over (order by field1, field2, field3) overall_order 
from ...
order by overall_order;

Both queries took a long time to run if I didn't not wait until this one is over. The question I have is the above two methods will return the same result in the same order? I know dense_rank() returns the same number of ranking if two values are the same, but do not know what 'order by' will do in the same situation.

I found that when the result set is small (say, a few hundred lines), the analytic function actually result in a higher cost to explain plan. Please let know us if it is OK to use the second method to achieve the effect of "order by" for the large result set.

If you have better alternatives, please suggest as well. Thank you.

Hello

Two of these methods do the same thing.

Both are for an indefinite period as to what happens when two or more rows have the same values for the three variables.
Say the lines A, B and C all have exactly the same values for field1, field2, and field3.
Say, you are running the version with ' ORDER BY Field1, Field2, formees3 ' and the output, in order, is A, B, C.
If you run one version, then there is no guarantee that you will again get the same order (A, B, C). You can get the same order, or you might not.

I'd be surprised if "ORDER BY overall_order" was faster than ' ORDER BY Field1, firld2, field3.

Tags: Database

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any case when and the sql clause
Hello:
What follows is my sql clause:
SELECT T.*, b.name
OF dbtest1 t
LEFT OUTER JOIN dbtest b ON t.NO = b.empno
WHERE t.ChineseName like '% "| : ChineseName | ' %' AND b.name like "%" | : name | » %'
ORDER BY t.ChineseName

The main problem is that I want to check the b.name if it is null, it can be passed as function NVL, so I try using case when, but it does not work.
When there are the b.name in where clause, the columns of result will not include data without b.name (or implies the b.name is NULL); And that
the result data are not entirely accurate.
is it possible to use the case when it is implemented in the following code snippet:

-case when b.name is not NULL then b.name like "%" | : name | » %'
Else b.name = NULL (b.name = b.name does not seem to work on the analysis of data zero)
end

Thank you very much.
962769 wrote:
The main problem is the table is the form of the cross, and the like clause will filter the
data without a name. Basically, it should show the empty columns, however, it won't.
so, when I test the sql code, I fhound Like "%" | b.Name | ' %' will not get the data when the original dbtest1 table data
has no id corresponding to the BD test. It seems pointless to go the LEFT OUTER JOIN.

Thank you
```
WHERE t.ChineseName like '%'||:ChineseName||'%'
AND  (
        b.name like '%'||:name||'%'
       or b.empno is null
    )
```

The USE of dynamic SQL clause
Hi all
I'm moving a table as a variable in dynamic SQl but with no result. Suppose that I it running on HR diagram example:
```
declare
sql_state varchar(100);
hire_date date;
temp_table varchar(9):='employees';

begin
sql_state:= 'select hire_date from :1 where employee_id=206';

execute immediate sql_state into hire_date using temp_table;
dbms_output.put_line('hire_date is '||hire_date);
end; 

declare
*
ERROR at line 1:
ORA-00903: invalid table name
ORA-06512: at line 9
```
I get this error of invalid table name without knowing what was read for the variable. Any advice?

Best regards
Val
Hi Valerie,

To add to what Peter, said

"Binding" values in a query is done for a specific purpose, and this purpose is so that the optimizer can use the same query as the previous execution plan runs the query, which prevent it from having to analyze the hard the query each time. A query execution plan is based on the tables and columns are presented in the query, but with respect to the actual "values" of these columns, they are unlikely to change the execution plan. So, to keep the same execution plan, the query must seem identical (in terms of a query string) like the previous series, so if you want the same query, but just with different values, they can be replaced with bind variables (these things have a ': ' character) and then the values passed in the query, when it is run.

Now, if Oracle were to allow you to link in the names of objects, such as tables, this means that it could not use the previous execution plans, because he doesn't know until run time what tables will be consulted. Therefore, it would be useless link in the values of the query and it would be just as quick to implement your query string by concatenating all the values inside rather than link them. Considering that a query is parsed first and then the values in it, then it cannot be analyzed if the tables are not known everything first. (Take a look at how queries are formed and variables when you use the DBMS_SQL package).

So the key thing to remember is that, when it comes to bind variables, you can bind only the 'values', not 'objects '.

These graphics cards are compatible with the computer

Hi I wonder if these graphics cards will be able to adapt and work in my machine

http://support.HP.com/us-en/document/c02628380

It's my computer

I wonder if these graphics cards are compatible have not decided what to buy yet

AMD Radeon R7 250 4 GB graphics card Sapphire Radeon R7 240 1 GB GDDR5, PCI-Express 3.0 (x 16) EVGA NVIDIA GeForce GT 730 1 GB GDDR5 graphics card

and also what power would be good for those or if I still have to improve diet

austin211,

If your return? Your other confectioners, Q, and r. Always try to find a card with a value of World of Warcraft? The recommended card is HD5870 or better. The cards that you offer are very low-end.

These startup programs are causing windows to start slowly

Original title: interruption of the performance issue
I installed the emulator DOSBox BACK on my computer slowed last January.It my computer. So I uninstalled. My computer became a little fast. But I always find a little problem. In the performance tools advanced it shows

Start up programs are causing Windows start slowly. See the details

When I click on it, I see that

______________________________________________________________________________<>

These startup programs are causing windows start slowly.

Name: BACK DOSBox emulator

File name: DOSBox.exe

Editor: DOSBox team

Day: Thu Jan 24,2013 14:55

Time of shooting: 109,7 seconds

______________________________________________________________________________>

This is the exact report I get. This report is boring. Help, please. I hope that my community.

Hello

Thanks for posting the request in the Microsoft community forums!
It seems that the computer is slow after installing the emulator DOSBox BACK. Don't worry, try the suggestions and check if it has speed up the computer.

What virus protection software is installed on the computer?

To solve the "'these startup programs are causing windows to start slowly ' error, try the methods"

Method 1:
Unplug external devices attached to the computer and then restart the computer and check the performance of the computer

Method 2:
Step 1: Check if the problem occurs in safe mode:
http://Windows.Microsoft.com/en-us/Windows7/start-your-computer-in-safe-mode
Step 2: If the problem does not occur in safe mode then you can perform a clean boot and check.

How to troubleshoot a problem by performing a clean boot in Windows Vista or in Windows 7
http://support.Microsoft.com/kb/929135
Note: After the adventures of shooting set the computer to start as usual by performing step 7 above of the Knowledge Base article.

Method 3:

You can run a Microsoft security scanner to make sure that the computer is free from virus infection:
http://www.Microsoft.com/security/scanner/en-us/default.aspx
WARNING:
If you run the antivirus program that is infected by the virus scan will get deleted. Therefore, reinstall the program. Also if the files and folders are affected by the virus, while they might even get deleted

See the link in order to improve the performance of the computer:

Optimize Windows 7 for better performance
http://Windows.Microsoft.com/en-us/Windows7/optimize-Windows-7-for-better-performance

Ways to improve your computer's performance
http://Windows.Microsoft.com/en-us/Windows7/ways-to-improve-your-computers-performance

If you need help with Windows, just tell me and we will be happy to help you.

Downloaded PSE13, these two files are located in the downloads folder, but I can't activate the program, he repeated to me that the part of the file is missing

Downloaded PSE13, these two files are located in the downloads folder, but I can't activate the program, he repeated to me that the part of the file is missing

Please check: https://forums.adobe.com/message/8163721

r beeb used before on pc. The problem is that these two PCs are thrown NAWL avay chrased long, I hava a few photos on the program and its impossible to buy a new number for one that oldc product. What should do?

r beeb used before on pc. The problem is that these two PCs are thrown NAWL avay chrased long, I hava a few photos on the program and its impossible to buy a new number for one that oldc product. What should do?

If you have the serial number, you can contact the Adobe Support via chat (when they are available - not weekend) and ask them to reset your activations. Which will allow you to reinstall and activate again using the serial number, which you have now.

To the link below, click on the still need help? the option in the blue box below and choose the option to chat...
Make sure that you are logged on the Adobe site, having cookies enabled, clearing your cookie cache. If it fails to connect, try to use another browser.

Serial number and activation support (non - CC) chat
https://helpx.Adobe.com/contact.html?step=PHSP-PHXS_downloading-installing-setting-up_lice nsing-activation_stillNeedHelp

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Mylenium

The following types are equivalent?
Hey guys, I want to know if an object type is equivalent to a record type. So ignore the problems of demarcation, the following types are equivalent?
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create or replace type xml_row as object (xmlfragment varchar2(2000));
/
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/
```
What I want to accomplish is the following equivalent
```
create or replace package pac_a as
  type xml_row is record(xmlfragment varchar2(2000));
  type xml_tab is table of xml_row;
end pac_a;
/ 
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From a point of view of 'data', the models are equivalent.
A type of object has a set of features that a classic record type has no, first the possibility to create a column in a table using this type...

Max

What are these SQL statements?

Hello!
We are our applications running on Windows Server 2003 where it works fine, using Oracle via OCI 12.1.
Now, we have the application installed on Windows Server 2012 and it works very slowly.
When comparing these two environments trace files came a surprise: Oracle generates a lot of SQL statements when run on Windows Server 2012! By operating on Windows2003 it only executes the SQL from the applicaton instructions. These additional SQL statements must be the reason for the slowness, but why Oracle it generates them and how could we get arrested?
An example:
PARSING IN CURSOR #46985062096816 len = 210 dep = 2 uid = 0 oct = cover 3 = 0 tim = hv 1439277877325893 = ad 864012087 = "4db599f28" sqlid = "96g93hntrzjtr."
Select / * + rule * / bucket_cnt, row_cnt, cache_cnt, null_cnt, timestamp #, sample_size, minimum, maximum, distcnt, lowval, hival, density, col #, spare1, spare2, hist_head avgcln $ where obj #=: 1 and intcol #=: 2
END OF STMT
ANALYSIS #46985062096816:c = 1000, e = 456, p = 0, cr = 0, cu = 0, put = 1, r = 0, dep = 2, og = 3, plh = 0, tim = 1439277877325890
EXEC #46985062096816:c = 0, e = 498, p = 0, cr = 0, cu = 0, put = 1, r = 0, dep = 2, og = 3, plh = 2239883476, tim = 1439277877326455
FETCH #46985062096816:c = 0, e = 56, p = 0, cr = 3, cu = 0, set = 0, r = 1, dep = 2, og = 3, plh = 2239883476, tim = 1439277877326533
STAT #46985062096816 id = 1 cnt = 1 pid = 0 obj = op 411 = pos = 1 "TABLE ACCESS BY INDEX ROWID HIST_HEAD$ (cr = 3 pr = 0 pw = time 0 = 55 US)"
"STAT #46985062096816 id = 2 cnt = 1 pid = 1 pos = 1 obj = op 413 ='INDEX RANGE SCAN I_HH_OBJ #_INTCOL # (cr = 2 pr = 0 pw = time 0 = 32 US)"
OUTCOME #46985062096816:c = 0, e = 37, dep = 2, type = 3, tim = 1439277877326601
EXEC #46985062096816:c = 0, e = 23, p = 0, cr = 0, cu = 0, set = 0, r = 0, dep = 2, og = 3, plh = 2239883476, tim = 1439277877326702
FETCH #46985062096816:c = 0, e = 18, p = 0, cr = 3, cu = 0, set = 0, r = 1, dep = 2, og = 3, plh = 2239883476, tim = 1439277877326738
OUTCOME #46985062096816:c = 0, e = 8, dep = 2, type = 3, tim = 1439277877326765
EXEC #46985062096816:c = 0, e = 19, p = 0, cr = 0, cu = 0, set = 0, r = 0, dep = 2, og = 3, plh = 2239883476, tim = 1439277877326837
FETCH #46985062096816:c = 0, e = 21, p = 0, cr = 3, cu = 0, set = 0, r = 1, dep = 2, og = 3, plh = 2239883476, tim = 1439277877326923
OUTCOME #46985062096816:c = 0, e = 10, dep = 2, type = 3, tim = 1439277877326954
Thank you very much in advance!
Best regards
Jaakko Terhonen

Thank you all for the reply! This time, the reason was a problem in network traffic (TCP protocol): a lot of retransmissions for a still unknown reason. If it had nothing to do with Oracle after all.

I cried for help here because as a common application programmer, I wasn't familiar with the Interior details of SQL analysis and after seeing it in the trace, I assumed that these strange SQL statements - which, for some reason, is appeared only in W2012-trace - were the reason for the slowness.

Thank you, I'm a little wiser now - and I hope that many others find this thread before asking the same question!

Best regards

Jaakko Terhonen

SQL clause 'or '.

Hello

I am creating a search function vi, which allows the user to search for some columns in my database with the input control 1. Is it possible to do if some of the columns have different data as string types & digital?

I have this here vi which I use to interrogate some of the column of the same type of data in the database. It seems that there is something wrong with my 'or' clause. When the input is b / l, the part of the data displayed is correct since the firstname column won't work & the clause "and" name also will not work, resulting in all data displayed. However, if I remove the or clause for my lastname, firstname column column will work but my data for the device will not work. When the input is 1, all occupants in my database will be displayed & they will all have the same unit even if they live in a different unit. However, if I delete my request first name, leaving only the unit, it works perfectly.

I believe that the problem happens if I use the or clause of these terms before the last clause "or" & after the last 'or' clause in my query will not work. The Address.AddID AND = PersonDetails.AddID AND PersonDetails.Status = 'active' is ignored if it is not the last clause 'or '.

IM using data select vi to recover my data, because it is something strange happens if I use the sql execute query vi. below is my sql query & attached is my base data & vi.

WHERE Address.Unit = 'b' or PersonDetails.FirstName LIKE '% b %' or PersonDetails.LastName LIKE '% b %' AND Address.AddID = PersonDetails.AddID AND PersonDetails.Status = 'active '.

Thanks for reading & hope someone knows why this happens.

Kind regards

Wayne

I can't open your files (got an earlier version), but I suppose you use an .mdb you have access? Do the work in question here? I have several times to build an access issue and switched to the sql mode to copy in LabView.

Maybe a couple of brackets to fix the problem. It should not be necessary, but it might help to use WHERE ([or CLAUSES]) AND ([CLAUSES AND])

/Y

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Remember - this is a public forum so never post private information such as numbers of mail or telephone!

Ideas:
- You have problems with programs
- Error messages
- Recent changes to your computer
- What you have already tried to solve the problem
On Monday, December 6, 2010 09:09:06 + 0000, krazychild18 wrote:

> Remember - this is a public forum so never post private information such as numbers of mail or telephone!

>

> Ideas: programs you have problems with error messages recent changes you do on your computer that you have already tried to solve the problem

Please do * not * leave the text above in a question to ask you. Delete it.

It has nothing to do with your question. And please ask your question

in the body of the message, not in the title.

How to get deleted? If you remove them normally, they must be

in the trash. If they are not, read point 1 below (but also pay

Special notice to the point 2):

1. "deleting" a file does not actually delete it just marks the

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the file is likely to be replaced very quickly, and it makes

the unrecoverable file.

So your chances of successfully recovering these files are decent if

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Ken Blake, Microsoft MVP

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Try tool Adobe Cleaner running:

Locate the Photoshop option and remove it.

Do not select clean all the option, it will remove all Adobe applications

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These SQL clauses are equivalent?

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