AND/OR TRUTH TABLE.

Is there any explanation for why
1) TRUE AND NULL = NULL
2) FALSE AND NULL = FALSE
3) TRUE OR NULL = TRUE
4) FALSE OR NULL = NULL
Thank you,
Narendra

Just to diagramatically show what Toon has explained...
It becomes clear if you jot down the logic tables and look at them yourself...
..X.. ..Y.. .AND.
TRUE TRUE   TRUE
TRUE FALSE FALSE
FALSE TRUE   FALSE
FALSE FALSE FALSEIf X is FALSE it doesn't matter if Y is unknown (NULL) because we know the truth table for AND
always gives a result of FALSE if X is FALSE. (no.2 in your list)
If X is TRUE, the result of AND logic becomes dependant on Y. If Y is unknown (NULL) then, the
answer is also unknown. (no.1 in your list)
..X.. ..Y.. .OR..
TRUE TRUE   TRUE
TRUE FALSE TRUE
FALSE TRUE   TRUE
FALSE FALSE FALSEIf X is TRUE it doesn't matter if Y is unknown (NULL) because we know the truth table for OR
always gives a result of TRUE if X is TRUE. (no.3 in your list)
If X is FALSE, the result of OR logic becomes dependant on Y. If Y is unknown (NULL) then, the
answer is also unknown (no.4 in your list)

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AND / OR truth table in SQL

why null is introduced in the AND and OR truth table?when will a statement/part of a statement return a null value??
|AND               |True          |False             |NULL??        |
|True               |True          |False             |Null             |
|False              |False          |False             |False           |
|Null                |Null             |Null               |Null             |is it introduced in AND/OR truth table for the null containing row(s)??
select employee_id,last_name,job_id,salary
from employees
wheere salary >= 1000
And job_id like '%man%';
how the statement after the where cluz can return null value??Edited by: sayantan chakraborty on Aug 14, 2009 11:36 AM

sayantan chakraborty wrote:
how either of X and Y will return a null value?can you put any example?is there any syntax/ command which will print the return value of a statement as null?Say you had a table with columns X and Y. As long as NOT NULL constraints WERE NOT defined these values could contain NULLs. Then if you apply the WHERE condition of X = Y you would have the case of NULL = NULL which results in UNKNOWN.
Simple Example:
SQL > WITH test_data AS
2 (
3          SELECT 1 AS X, 1 AS Y FROM DUAL UNION ALL
4          SELECT 2 AS X, 2 AS Y FROM DUAL UNION ALL
5          SELECT 3 AS X, 5 AS Y FROM DUAL UNION ALL
6          SELECT 4 AS X, 6 AS Y FROM DUAL UNION ALL
7          SELECT 1 AS X, NULL AS Y FROM DUAL
8 )
9 SELECT *
10 FROM    test_data
11 WHERE   X = Y
12 /
         X          Y
         1          1
         2          2

I need some working examples with pl/sql records and pl/sql tables.

i am new to pl/sql tables and pl/sql records. i need some working examples on pl/sql records and pl/sql tables from basics to hoghlevel.how to use then procedures and functions and packages.

i am new to pl/sql tables and pl/sql records. i need some working examples on pl/sql records and pl/sql tables from basics to hoghlevelThere is no such thing as PL/SQL "+tables+". This is a misnomer and creates the perception that a PL/SQL "table" is somewhat like a SQL table. Nothing can be further from the truth. The correct term is "+collection+" or "+associative array+". Compared to SQL tables, these are very primitive structures, very rigid structures, cannot scale, and can be quite expensive memory wise.
That is not to say do not use an associative array or collection. These are very useful tools.. but only when applied correctly. Like using a collection for a bulk fetch to transfer more rows between the PL and SQL engines and thus decrease context switching.
Unfortunately, quite often we see the row-by-row and slow-by-slow approach - where the developer uses SQL as an I/O only layer, pulls rows into expensive PL engine memory into record structures and arrays, and then process the rows there.
So before looking at working example (even the wrong approach's code will compile and run and work in practice), make sure that you know the fundamentals of correctly using the PL engine and correctly using the SQL engine. And these fundamentals can be summed up into a very basic rule:
Maximize SQL. Minimize PL/SQL+
Get this rule right, and you will have a sound foundation for writing performant and scalable Oracle applications.

Truth Tables

I have to do an assignment for my computer programming class
regarding truth tables and I do not understand the concept behind
it all. If someone can give me an explanation of this, I would
really be thankful. You can find the assignment
here. I just
don't get it.

A truth table is a matrix (no not a movie). Say you have an
alarm on a chicken coop door and you want to know when the chickens
are in the coop and when the door is open to warn you that a fox
could get in. The truth table shows the states of the door (open or
closed) and the states of the chickens (in or out). so your truth
table would be:
doorOpen doorClosed
chickensIn 1 0
chickensOut 0 0
the only time the alarm would go off is when the chicken are
in the coop and the door is open. so your code would be:
if (chickensIn and doorOpen) {goCleseThe Door;}

Diff b/w select endselect and select into table............

what is the difference b/w
Select
Endselect
and select into table....
Akshitha..

Hi,
When ever u want to append data into the workarea then use select ... endselect. When u r appending data into the internal table then use select. Also when u use select single then also use only select.
Eg: Using only Select
data : begin of itab occurs 0,
lifnr like lfa1-lifnr,
end of itab.
select single lifnr from lfa1 into itab.
data itab like lfa1 occurs 0 with header line.
select * from lfa1 into table itab.
Eg: Using Select .. endselect.
data : itab like lfa1 occurs 0,
wa like lfa1.
select * from lfa1 into wa.
append wa to itab.
endselect.
Regards

Creating tables on SQL studio and viewing the table in the SAP system

i have just created a table using the SQL studio and wants to use it view it in the SAP system using the SAP logon. till now i have not found a way to create it therefore any help is much appreciated.

Hmm... you want to see tables via SAPLogon ??
Ok, let's assume you really want to access tables via ABAP instead.
For that you've two options:
1. Create the table in the ABAP dictonary (SE11) exactly like you created it in the database and activate the table.
After that you can access the table via SE16 or any ABAP as you like.
2. You don't create the table in the ABAP dictonary and use native SQL to access the data.
Neither of these options is meant to be the way to do it.
The correct way would be to design the whole table in the ABAP dictionary and create the table on the database from that.
regards,
Lars

Purchase order and sales order table name

hi al,
i want to know purchase order and sales order table name in abap.
thanks
varun
Moderator message: please do some own research, this should not take too long.
Edited by: Thomas Zloch on Jan 27, 2012

Hi Sunrag......
If your PO is linked with SO. Then you can fetch customer name easily by FMS in PO.
From there you ca gte the Customer Name into your PLD and it wont hang also.....
Regards,
Rahul

Analysing and Updating a table

Hi,
Can anyone help me on follwing query..
Can analyse of a table and updation on to same table can happen paralley?
thank in advance.

What's your db version? The very first thing is that you should not use the analyze command but dbms_stats package. Now , I am not sure why you want to gather the stats and update the table at the same time? As mentioned by Erica, the update should be followed with the stats gathering. And about the index usage, there are couple of things that can stop index from being used, for example, low selectivity on the column can very well stop the index. Other than that, if you are accessing the column containing the index alone and the column is supposed to contain the null values, oracle would rather use a FTS than using the index which actually makes perfect sense since use of index would result in incorrect data. So there can be couple of htings possible which may stop your index from being used. All what dbms_stats(and even Analyze) command would do , is to make the distribution of the data known tooracle. Having stats alone doesn't guarantee that the index would be used for sure.
HTH
Aman....

How to repeat Header and Footer's table on each page

Hi all of you,
I have to create an invoice form which look alike the Purchase order forms example provided by Adobe.
In the table object, i set up exactly the same attribute as the example but i didn't manage to get the same result :
- the table is nested in a subformular which attribute is Flowed + Page Break.
- Header and Footer's table are set up such as they should be repeated on every page.
I work on the Adobe Life cycle 8.01 and ECC 6.0.
Thanks for the help

Hi Vincent,
Use the Create Table assistence while you creating the table, there you will specify the header and footer
Change the table type as flowed in object tab.
Then select the Header Row in Hierarchy tab and go to the Pagination in object tab
there you check Include Header Row in Subsequent Pages and same as footer.
By
Parthi

Populate and display internal table results using search help exit...

I have copied F4IF_SHLP_EXIT_EXAMPLE and made changes. I want this search help exit to populate and display contents related to 'FIELD1' when the user enters a specific value for it in the search help screen, meaning when the user restricts the search by that value. For field2, field3, field4, field5, field6, field7, and field8 I am using a custom view.
Following is the code:
TYPES: BEGIN OF t_search,
               field2 TYPE field2,
               field3 TYPE field3,
               field4 TYPE field4,
               field5 TYPE field5,
               field6 TYPE field6,
               field7 TYPE field7,
               field8 TYPE field8,
               field1 TYPE field1,
            END OF t_search.
DATA: it_itab TYPE TABLE OF t_search,
        wa TYPE t_search,
     wa_selopt TYPE ddshselopt,
        wa_fielddescr TYPE dfies.
ranges: r_field1 for std_table1-field1
STEP SELECT    (Select values)
    FREE: r_field1.
**Get the value entered for FIELD1 in search help
    LOOP AT shlp-selopt INTO wa_selopt.
      CASE wa_selopt-shlpfield.
        WHEN 'FIELD1'.
          r_field1-sign = wa_selopt-sign.
          r_field1-option = wa_selopt-option.
          r_field1-low = wa_selopt-low.
          r_field1-high = wa_selopt-high.
          APPEND r_field1.
          CLEAR: r_field1.
      ENDCASE.
    ENDLOOP.
**Select 'ID' and 'FIELD1' from table into lt_itab
    SELECT id field1
          INTO TABLE lt_itab
            FROM std_table1
              WHERE field1 IN r_field1.
    IF sy-subrc = 0.
**Now, based on the particular IDs from lt_itab, I need to select other values
from other tables which also have 'ID' as the key.
       SELECT std_table2~field2
            std_table2~field3
            std_table3~field4
            std_table3~field5
            std_table3~field6
            std_table4~field7
            std_table4~field8
            std_table1~field1
          INTO CORRESPONDING FIELDS OF TABLE it_itab
          FROM std_table2
                     INNER JOIN std_table3 ON
                            std_table3mandt = std_table2mandt AND
                            std_table3id = std_table2id
                     INNER JOIN std_table4 ON
                            std_table4mandt = std_table2mandt AND
                            std_table4id = std_table2id
                     INNER JOIN std_table1 ON
                            std_table1mandt = std_table2mandt AND                                           std_table1id = std_table2id
          WHERE
                std_table1~field1 IN r_field1.
'id' is common in all the std_tables --> std_table1, std_table2, std_table3, std_table4.
STEP DISP     (Display values)
**Then I need to gather all the results in my internal table it_itab and display
in search help results for the value of FIELD1 entered by the user in the search help.
    CALL FUNCTION 'F4UT_PARAMETER_RESULTS_PUT'
      EXPORTING
        parameter   = 'FIELD1'
        fieldname   = 'FIELD1'
      TABLES
        shlp_tab    = shlp_tab
        record_tab = record_tab
        source_tab = it_itab
      CHANGING
        shlp        = shlp
        callcontrol = callcontrol.
I am not getting all the data in my internal table and wanted to know if there is anyting wrong in my select statement.
Any guidance will be appreciated and awarded appropriate points.
Thanks.

the webdynpro fieldname and the search help input parameter name were made same.

Exporting and importing just table definitions

Hi,
I have this production database that has a huge amount of data in it. I was asked to set up a test database based on the exact same schema as the live database. When I tried to do an export (from live) and import (to test), with the parameters rows=N and compress=y, the target (test database) data file will still grow enormously, presumably because of the huge number of extents already allocated to the table in the live database. My test database of course, has a limited hard-disk space.
Is there a way to export and import the table definitions without having the target database experiencing a huge growth in the size of the tablespace?
Thanks,
Chris.

If an export with compress=n is still creating initial extents that a too large, you can still build with the import file but it will take a little work.
run imp with indexfile=somefile.sql
when imp is finished, edit somefile.sql by:
1. remove all the REM statements.
2. remove all the storage clauses (tables and indexes)
Make sure your tablespaces have a small (say 1k) default initial extent.
run imp again with rows=n
All your tables and indexes will be created with the default tablespace initial extent.

SQL Server 2012 Management Studio:In the Database, how to print out or export the old 3 dbo Tables that were created manually and they have a relationship for 1 Parent table and 2 Child tables?How to handle this relationship in creating a new XML Schema?

Hi all,
Long time ago, I manually created a Database (APGriMMRP) and 3 Tables (dbo.Table_1_XYcoordinates, dbo.Table_2_Soil, and dbo.Table_3_Water) in my SQL Server 2012 Management Studio (SSMS2012). The dbo.Table_1_XYcoordinates has the following columns: file_id,
Pt_ID, X, Y, Z, sample_id, Boring. The dbo.Table_2_Soil has the following columns: Boring, sample_date, sample_id, Unit, Arsenic, Chromium, Lead. The dbo.Table_3_Water has the following columns: Boring, sample_date, sample_id, Unit, Benzene, Ethylbenzene,
Pyrene. The dbo.Table_1_XYcoordinates is a Parent Table. The dbo.Table_2_Soil and the dbo.Table_3_Water are 2 Child Tables. The sample_id is key link for the relationship between the Parent Table and the Child Tables.
Problem #1) How can I print out or export these 3 dbo Tables?
Problem #2) If I right-click on the dbo Table, I see "Start PowerShell" and click on it. I get the following error messages: Warning: Failed to load the 'SQLAS' extension: An exception occurred in SMO while trying to manage a service.
--> Failed to retrieve data for this request. --> Invalid class. Warning: Could not obtain SQL Server Service information. An attemp to connect to WMI on 'NAB-WK-02657306' failed with the following error: An exception occurred in SMO while trying
to manage a service. --> Failed to retrieve data for this request. --> Invalid class. .... PS SQLSERVER:\SQL\NAB-WK-02657306\SQLEXPRESS\Databases\APGriMMRP\Table_1_XYcoordinates>   What causes this set of error messages? How can
I get this problem fixed in my PC that is an end user of the Windows 7 LAN System? Note: I don't have the regular version of Microsoft Visual Studio 2012 in my PC. I just have the Microsoft 2012 Shell (Integrated) program in my PC.
Problem #3: I plan to create an XML Schema Collection in the "APGriMMRP" database for the Parent Table and the Child Tables. How can I handle the relationship between the Parent Table and the Child Table in the XML Schema Collection?
Problem #4: I plan to extract some results/data from the Parent Table and the Child Table by using XQuery. What kind of JOIN (Left or Right JOIN) should I use in the XQuerying?
Please kindly help, answer my questions, and advise me how to resolve these 4 problems.
Thanks in advance,
Scott Chang

In the future, I would recommend you to post your questions one by one, and to the appropriate forum. Of your questions it is really only #3 that fits into this forum. (And that is the one I will not answer, because I have worked very little with XSD.)
1) Not sure what you mean with "print" or "export", but when you right-click a database, you can select Tasks from the context menu and in this submenu you find "Export data".
2) I don't know why you get that error, but any particular reason you want to run PowerShell?
4) If you have tables, you query them with SQL, not XQuery. XQuery is when you query XML documents, but left and right joins are SQL things. There are no joins in XQuery.
As for left/right join, notice that these two are equivalent:
SELECT ...
FROM   a LEFT JOIN b ON a.col = b.col
SELECT ...
FROM   b RIGHT JOIN a ON a.col = b.col
But please never use RIGHT JOIN - it gives me a headache!
There is nothing that says that you should use any of the other. In fact, if you are returning rows from parent and child, I would expect an inner join, unless you want to cater for parents without children.
Here is an example where you can study the different join types and how they behave:
CREATE TABLE apple (a int    NOT NULL PRIMARY KEY,
b varchar(23) NOT NULL)
INSERT apple(a, b)
   VALUES(1, 'Granny Smith'),
   (2, 'Gloster'),
   (4, 'Ingrid-Marie'),
   (5, 'Milenga')
CREATE TABLE orange(c int NOT NULL PRIMARY KEY,
d varchar(23) NOT NULL)
INSERT orange(c, d)
   VALUES(1, 'Agent'),
   (3, 'Netherlands'),
   (4, 'Revolution')
SELECT a, b, c, d
FROM   apple
CROSS JOIN orange
SELECT a, b, c, d
FROM   apple
INNER JOIN orange ON apple.a = orange.c
SELECT a, b, c, d
FROM   apple
LEFT   OUTER JOIN orange ON apple.a = orange.c
SELECT a, b, c, d
FROM   apple
RIGHT OUTER JOIN orange ON apple.a = orange.c
SELECT a, b, c, d
FROM   apple
FULL OUTER JOIN orange ON apple.a = orange.c
go
DROP TABLE apple, orange
Erland Sommarskog, SQL Server MVP, [email protected]

How can one read a Excel File and Upload into Table using Pl/SQL Code.

How can one read a Excel File and Upload into Table using Pl/SQL Code.
1. Excel File is on My PC.
2. And I want to write a Stored Procedure or Package to do that.
3. DataBase is on Other Server. Client-Server Environment.
4. I am Using Toad or PlSql developer tool.

If you would like to create a package/procedure in order to solve this problem consider using the UTL_FILE in built package, here are a few steps to get you going:
1. Get your DBA to create directory object in oracle using the following command:
create directory TEST_DIR as ‘directory_path’;
Note: This directory is on the server.
2. Grant read,write on directory directory_object_name to username;
You can find out the directory_object_name value from dba_directories view if you are using the system user account.
3. Logon as the user as mentioned above.
Sample code read plain text file code, you can modify this code to suit your need (i.e. read a csv file)
function getData(p_filename in varchar2,
p_filepath in varchar2
) RETURN VARCHAR2 is
input_file utl_file.file_type;
--declare a buffer to read text data
input_buffer varchar2(4000);
begin
--using the UTL_FILE in built package
input_file := utl_file.fopen(p_filepath, p_filename, 'R');
utl_file.get_line(input_file, input_buffer);
--debug
--dbms_output.put_line(input_buffer);
utl_file.fclose(input_file);
--return data
return input_buffer;
end;
Hope this helps.

How do I transpose and group a table in a ViewObject?

Hi,
I want to transpose and group a table within a view object and don't know how to do it.
Please let me explain what I want to do:
One table, e.g. Employees, has one row per employee. Each employee has a departmenent and a room assigned:
Employee
Department
Room
John
Finance
101
Susie
Prod
102
Hank
Finance
103
Now I want to show one row per departmenent and a marked checkbox for each room that has an employee from this department in it:
Department
Room 101
Room 102
Room 103
Finance
X
X
Prod
X
What I already did is, I added a transient attribute of type boolean for each room to the ViewObject for employees. I was able to set the booleans within the method ViewObject::createRowFromResultSet. But I still need to do a grouping by department.
What I don't understand is: is it possible to 1. selecting data, 2. grouping the result and 3. setting booleans for the rooms, anything in the same view object? Or do I need to have two ViewObjects, one that holds the data and another one that prepares and to displays the data?
Btw. the users will change the checkboxes and the changes must be written back to the database (makes no sense for this example, I know...).
Could anything be done in the same ViewObject? If so, which methods do I have to overwrite to do the grouping?
Could someone please give me a hint or let me know where I can find an example of a similar scenario?
Thanks in advance!

Sort the playlist into the desired order, e.g. click the heading for the track no. or album columns, the right-click on the playlist name and click Copy to Play Order. The playlist should now burn in the correct order.
tt2

How to export and import dependent tables from 2 different schema

I have a setup where schema1 has table 1 and schema 2 has table2. And table 1 from schema1 depends upon table 2 from schema 2.
I would like to export and import these tables only and not any other tables from these 2 schemas with all information like grants,constraints.
Also will there be same method for Oracle 10g R1,R2 and Oracle 11G.
http://download.oracle.com/docs/cd/B12037_01/server.101/b10825/dp_export.htm#i1007514
Looking at this For table mode it says
Also, as in schema exports, cross-schema references are not exported
Not sure what this means.
As I am interested in only 2 tables I think I need to use table mode. But if I try to run export with both tables names, it says table mode support only one schema at a time. Not sure then How would the constraints would get exported in that case.
-Rohit

worked for my 1st time I tried
exp file=table2.dmp tables="dbadmin.temp1,scott.emp"
Export: Release 10.2.0.1.0 - Production on Mon Mar 1 16:32:07 2010
Copyright (c) 1982, 2005, Oracle. All rights reserved.
Username: / as sysdba
Connected to: Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production
With the Partitioning, OLAP and Data Mining options
Export done in US7ASCII character set and AL16UTF16 NCHAR character set
server uses WE8ISO8859P1 character set (possible charset conversion)
About to export specified tables via Conventional Path ...
Current user changed to DBADMIN
. . exporting table TEMP1 10 rows exported
EXP-00091: Exporting questionable statistics.
Current user changed to SCOTT
. . exporting table EMP 14 rows exported
EXP-00091: Exporting questionable statistics.
EXP-00091: Exporting questionable statistics.
Export terminated successfully with warnings.

AND/OR TRUTH TABLE.

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