Table-like Data Structure

I'm trying to develop an application where I require 2 or more store equivalent objects. Each object has an id (int) used as part of the hashCode() and equals() methods. I would like to store all objects in a data structure that would allow to store and easily retrieved the concepts based on either id. I have thought about using TreeMap or Hashtable but those only allow the retrieval of element using the key.

In description logic, we can express statements, such as A := C, meaning that A and C are equivalent (i.e. the same object). I would like to keep track of these objects to reduce the number of iteration carried by the algorithm. If I store these elements in a java.util.Hashtable<K,V> then I'm only allowed to retrieve objects using the key (i.e. Hashtable.get(Object key)). However, I need to be able to retrieve elements either by keys or values depending on the task. For example, if I find C in another statement I would like to replace it by A and sometimes I need to use A to retrieve C.

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Hashtable like data structure

I am just trying to find out if anyone knows of a data structure that is similar to a hashtable, with the exception that I need to be able to access a KEY given a VALUE, as well as the standard access of a VALUE given a KEY.
Hashtable only allows lookup by KEY, not VALUE.
Thanks, Jason

And not only that, Hashtable allows more than one key to have the same value. The simplest solution (not algorithm) for your problem is an object that wraps two Hashtables, one to handle the A->B mapping and the other to handle the B->A mapping.
Unless your mappings are not 1-to-1, such as if you had A,B and C,D and E,B in which case your value-to-key mapping for value B would somehow have to return both A and E.

Updating a hierarchical data structure from an entry processor

I have a tree-like data structure that I am attempting to update from an AbstractProcessor.
Imagine that one value is a collection of child value keys, and I want to add a new child node in the tree. This requires updating the parent node (which contains the list of child nodes), and adding the child value which is a separate entry.
I would rather not combine all bits of data into one value (which could make for a large serialized object), as sometimes I prefer to access (read-only) the child values directly. The child and the parent values live in the same partition in the partitioned cache, though, so get access should be local.
However, I am attempting to call put() on the same cache to add a child value which is apparently disallowed. It makes sense that a blocking call is involved in this operation, as it needs to push out this data to the cluster member that has the backup value for the same operation, but is there a general problem with performing any kind of re-entrant work on Coherence caches from an entry processor for any value that is not the value you are processing? I get the assertion below.
I am fine with the context blocking (preventing reads or writes on the parent node value) until the child completes, presuming that I handle deadlock prevention myself due to the order in which values are accessed.
Is there any way to do this, either with entry processors or not? My code previously used lock, get and put to operate on the tree (which worked), but I am trying to convert this code to use entry processors to be more efficient.
2008-12-05 16:05:34.450 (ERROR)[Coherence/Logger@9219882 3.4/405]: Assertion failed: poll() is a blocking call and cannot be called on the Service thread
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.Grid.poll(Grid.CDB:4)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.Grid.poll(Grid.CDB:11)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.DistributedCache$BinaryMap.put(DistributedCache.CDB:30)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.DistributedCache$BinaryMap.put(DistributedCache.CDB:1)
     at com.tangosol.util.ConverterCollections$ConverterCacheMap.put(ConverterCollections.java:2433)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.DistributedCache$ViewMap.put(DistributedCache.CDB:1)
     at com.tangosol.coherence.component.util.SafeNamedCache.put(SafeNamedCache.CDB:1)
     at com.tangosol.net.cache.CachingMap.put(CachingMap.java:928)
     at com.tangosol.net.cache.CachingMap.put(CachingMap.java:887)
     at com.tangosol.net.cache.NearCache.put(NearCache.java:286)
     at com.conduit.server.properties.CLDistributedPropertiesManager$UpdatePropertiesProcessor.process(CLDistributedPropertiesManager.java:249)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.DistributedCache$Storage.invoke(DistributedCache.CDB:20)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.DistributedCache.onInvokeRequest(DistributedCache.CDB:50)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.DistributedCache$InvokeRequest.run(DistributedCache.CDB:1)
     at com.tangosol.coherence.component.net.message.requestMessage.DistributedCacheKeyRequest.onReceived(DistributedCacheKeyRequest.CDB:12)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.Grid.onMessage(Grid.CDB:9)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.Grid.onNotify(Grid.CDB:130)
     at com.tangosol.coherence.component.util.daemon.queueProcessor.service.grid.DistributedCache.onNotify(DistributedCache.CDB:3)
     at com.tangosol.coherence.component.util.Daemon.run(Daemon.CDB:37)
     at java.lang.Thread.run(Thread.java:637)

Hi,
reentrant calls to the same Coherence service is very much recommended against.
For more about it, please look at the following Wiki page:
http://wiki.tangosol.com/display/COH34UG/Constraints+on+Re-entrant+Calls
Best regards,
Robert

Comparing Data between two tables with different structure

Hi,
I have 2 tables T1 and T2. Both tables have different structure. I have to check for rows missing in T1 which exist in T2 and vice-versa. I can do that using MINUS operator. But the part where the data exists in both T1 and T2, I have to compare some columns (9 columns the names of this column coming from a meta-data table) if they have same values. If not an exception has to be generated.
Any help is appreciated.
Thanks

Hi,
Whenever you need help on this forum, post:
(1) The version of Oracle (and any other relevant software) you're using
(2) A little sample data (just enough to show what the problem is) from all the relevant tables
(3) The results you want from that data (4) Your best attempt so far
Executable SQL statements (like "CREATE TABLE AS ..." or "INSERT ..." statements) are best for (2).
Formatted tabular output is okay for (3). Type before and after the tabular text, to preserve spacing.
What do you mean by "an exception has to be generated"?
Do you want to raise an error?
Do you want something to appear in the result set?
MINUS finds rows that are in one result set, but not in another.
INTERSECT finds rows that are in both result sets.
Column names have to be hard-coded into the SQL statement. If you want to write something now that will get column names from a metadata table sometime in the future, then you have to use dynamic SQL. SQL*Plus sometimes has quick and dirty ways of doing dynamic SQL, so say whether you're using SQL*Plus or not.

How to Copy complete structure of a table with data from one database table to another databse table

I need a sql query to copy structure of table with data from production table of ONLINEBTREKDB database to production table of Archive database.
I tried this query
select * into Archive.dbo.Production from ONLINEBTREKDB.dbo.Production p
but problem is I am able to copy the table schema and data but not able to copy constraints(PK)
Any Help?
seema

You've multiple options
1. Use generate scripts wizard available in SQL management studio. This is particularly helpful when you want to script out lot of objects. You can also choose to script data as well inside this. This can be launched by right clicking the db, choosing tasks
-> generate scripts and then selecting required options inside the wizard
2. Use object explorer and right click and script out table. You can also use search functionality to find object you want inside object explorer
http://visakhm.blogspot.in/2013/02/object-filtering-using-ssms-object.html
3. Use query based on INFORMATION_SCHEMA views like TABLES,COLUMNS,CONSTRAINT_COLUMN_USAGE etc to generate the script
Please Mark This As Answer if it helps to solve the issue Visakh ---------------------------- http://visakhm.blogspot.com/ https://www.facebook.com/VmBlogs

A data structure to represent a table in ram ?

So I've implemented a shoppingCart using a table in the database and it's fine.
BUT, I'm thinking the table approach isn't that efficient - for example clicking Add to Cart does two things:
1) insert the row into the shoppingCart table
2) display the whole shopping cart for that session
I'm thinking, wouldn't it be nice if I could just store the shoppingCart in a data structure ? I'm sure Coldfusion supports such a strucuture with addRow , removeRow commands - I just can't think of it.
Do you think this is an efficient approach ?

a data structure to represent a table in ram ?
Yes. In fact, you could literally use a structure to represent the shopping-cart in memory. It would begin like this:
<cfset session.shoppingCart = structnew()>
I'm sure Coldfusion supports such a strucuture with addRow , removeRow commands - I just can't think of it.
You would then be thinking of structInsert() and structDelete.
Do you think this is an efficient approach ?
Yes. However, I have a different suggestion. What you're doing is a learning exercise. That can only be a good thing.
If you're serious about setting up shop, which I assume you are, then you should invest in shopping-cart software. They cost little, relative to the benefit you could derive from them. Mary Jo's CFWebstore seems good value for money.

Differrences between structure and table in data dictionary in ABAP?

What is the differrences between structure and table in data dictionary in ABAP?
are they same?

Tables :
1. The place where the data is stored so that you can retrieve at any time.
2. There can be more than one record stored
Structures :
1. The data / info stays only during the runtime of the application and will not get stored at all during the run time ....
2. Only one record can be stored at the runtime .....
A structure forms the skeleton of the table.
A structure comprises components i.e., fields. Types are defined for the components A component can refer to an elementary type (via a data element or by directly specifying the data type and length in the structure definition), another structure or a table type. A structure can therefore be nested to any depth
Tables can be defined independently of the database in the ABAP Dictionary. The fields of the table are defined with their (database-independent) data types and lengths.
When the table is activated, a physical table definition is created in the database for the table definition stored in the ABAP Dictionary. The table definition is translated from the ABAP Dictionary to a definition of the particular database.

SQL 2008 how to compare & identify data among 2 tables with same structure ?

Hello is there a TSQL way of comparing row by row for example comparing DateTimeStamp field in 2 separate tables with same structure in identifying if it's data was changed (If Table1.DateField > Table2.DateField THEN UPDATE it's entire row to match it's
corresponding Table1 row.) ?
Probably thinking would need a cursor to loop through or are there other better ways via TSQL ?
Thanks in advance.

Hi,
I am assuming you have a PRIMARY KEY field or a UNIQUE field in both tables, which you should!
You can do this using "UPDATE with INNER JOIN". (SQL Server – Update Table with INNER JOIN)
Working example:
USE [TestDatabase]
GO
/* Create Temp Tables */
CREATE TABLE [dbo].[Table1]
[ID] INT
,[Name] VARCHAR(10)
,[ModifyDate] DATETIME
CREATE TABLE [dbo].[Table2]
[ID] INT
,[Name] VARCHAR(10)
,[ModifyDate] DATETIME
GO
INSERT INTO [dbo].[Table1] ([ID], [Name], [ModifyDate]) VALUES (1, 'Vishal', GETDATE())
INSERT INTO [dbo].[Table2] ([ID], [Name], [ModifyDate]) VALUES (1, 'Gajjar', GETDATE() + 1)
GO
SELECT [ID], [Name], [ModifyDate] FROM [dbo].[Table1]
SELECT [ID], [Name], [ModifyDate] FROM [dbo].[Table2]
GO
UPDATE T1
SET T1.[Name] = T2.[Name]
FROM [dbo].[Table1] T1
INNER JOIN [dbo].[Table2] T2 ON T1.[ID] = T2.[ID] /* Join on Key field */
WHERE T2.[ModifyDate] > T1.[ModifyDate] /* Update criteria */
GO
/* CleanUp - Drop Tables
DROP TABLE [dbo].[Table1], [dbo].[Table2]
This Updates Table1 with latest values from Table2, You need to change the UPDATE statement for your scenario.
- Vishal
SqlAndMe.com

Data structure similar to database table

i have the need for a data structure that will essentially be the same as a database table. this "table" can be queried against and sorted.
currently, i am using an interface to abstract this "table" datastructure, and implementing the interface via jdbc calls.
may someone point me in the right direction?
in .NET, they have the DataTable and DataSet data structures, which do exactly as i require. These are objects essentially correspond to a database table and database, respectively. They are used as in-memory database.
i have already tried using HSQL, but was wondering if there was a "better" way (i.e. more light-weight, intuitive, easier to use).
thanks.

Use an array and put your records in it.
Efficient querying (simple queries) requires you to build indices for each element you wish to query on. The type of index depends on the kind on search you want to perform. Exact matches can use Hashes. Sorting, prefix or postfix matching can be performed using various tree indices.
Complex queries (i.e. those that query on multiple parameters generally require query optimisers to figure out how to use the indies you have in the most efficient manner possible (well as close as the optimizer can get to it).
cheers
matfud

How the data populated into tables like USR01,USR02 etc

Hi,
I have one theoritical doubt. How the data is populated into tables like USR01, USR02 etc after creating the
user using SU01. Let me know the process behind it.
Rgds,
Chandra.

Hi Chinna,
When you create users using SU01, SU10 transaction codes, it uses BAPI_USER_CREATE1 which will update the data in the respective tables.
Same way BAPI_USER_CHANGE is used when you modify any existing users.
Hope this answers!!
Warm Regards,
Raghu

MRS for Data structure table

I need to various data structure table for MRS

A possible solution is create a materialized view and then a check constraint on the materialized view: this should work in a multiuser environment.
Example:
SQL> drop table t;
Table supprimee.
SQL>
SQL> create table t (
2 x integer,
3 y varchar2(10)
4 );
Table creee.
SQL>
SQL> CREATE MATERIALIZED VIEW LOG on t
2 WITH ROWID (x, y)
3 including new values;
Journal de vue materialisee cree.
SQL>
SQL> CREATE MATERIALIZED VIEW t_mv
2 REFRESH FAST ON COMMIT AS
3 SELECT count(*) cnt
4 FROM t;
Vue materialisee creee.
SQL>
SQL> ALTER TABLE t_mv
2 ADD CONSTRAINT chk check(cnt<=1);
Table modifiee.
SQL>
SQL> insert into t values(1,'Ok');
1 ligne creee.
SQL> commit;
Validation effectuee.
SQL>
SQL> insert into t values(2,'KO');
1 ligne creee.
SQL> commit;
commit
ERREUR a la ligne 1 :
ORA-12008: erreur dans le chemin de regeneration de la vue materialisee
ORA-02290: violation de contraintes (TEST.CHK) de verification

How can i compare 2 internal table's data which have same structure ?

hi friends,
i want to know how to compare 2 internal table's data which have same structure

DATA: BEGIN OF LINE,
COL1 TYPE I,
COL2 TYPE I,
END OF LINE.
DATA: ITAB LIKE TABLE OF LINE,
JTAB LIKE TABLE OF LINE.
DO 3 TIMES.
LINE-COL1 = SY-INDEX.
LINE-COL2 = SY-INDEX ** 2.
APPEND LINE TO ITAB.
ENDDO.
MOVE ITAB TO JTAB.
LINE-COL1 = 10. LINE-COL2 = 20.
APPEND LINE TO ITAB.
IF ITAB GT JTAB.
WRITE / 'ITAB GT JTAB'.
ENDIF.
APPEND LINE TO JTAB.
IF ITAB EQ JTAB.
WRITE / 'ITAB EQ JTAB'.
ENDIF.
LINE-COL1 = 30. LINE-COL2 = 80.
APPEND LINE TO ITAB.
IF JTAB LE ITAB.
WRITE / 'JTAB LE ITAB'.
ENDIF.
LINE-COL1 = 50. LINE-COL2 = 60.
APPEND LINE TO JTAB.
IF ITAB NE JTAB.
WRITE / 'ITAB NE JTAB'.
ENDIF.
IF ITAB LT JTAB.
WRITE / 'ITAB LT JTAB'.
ENDIF.
The output is:
ITAB GT JTAB
ITAB EQ JTAB
JTAB LE ITAB
ITAB NE JTAB
ITAB LT JTAB
This example creates two standard tables, ITAB and JTAB. ITAB is filled with 3 lines and copied to JTAB. Then, another line is appended to ITAB and the first logical expression tests whether ITAB is greater than JTAB. After appending the same line to JTAB, the second logical expression tests whether both tables are equal. Then, another line is appended to ITAB and the third logical expressions tests whether JTAB is less than or equal to ITAB. Next, another line is appended to JTAB. Its contents are unequal to the contents of the last line of ITAB. The next logical expressions test whether ITAB is not equal to JTAB. The first table field whose contents are different in ITAB and JTAB is COL1 in the last line of the table: 30 in ITAB and 50 in JTAB. Therefore, in the last logical expression, ITAB is less than JTAB.
regards,
srinivas
<b>*reward for useful answers*</b>

Tcode to populate data in to demo tables like SPFLI, SFLIGHT,SBOOK?

Can you please let me know the tcode to populate data in to demo tables like SPFLI, SFLIGHT,SBOOK etc

Run this program S_FLIGHT_MODEL_DATA_GENERATOR
In ecc 6.0 this program is available? it is saying it does not exist.
Regards,
Vishwa.

HOW TO MOVE DATA FROM INT-TABLE TO DATABASE STRUCTURE?

DEAR ALL!
CAN ANY ONE GIVE ME SAMPLE CODE TO MOVE DATA FROM INT -TABLE TO DB-STRUCTURE PLEASE.
I HAVE THE VALUES IN TABLE AND I NEED TO UPDATE STRUCTURE.
REGARDS,
VJ

Hi,
If you want to update a db STRUCTURE it is not possible because Structure doesnot hold any data.
If you are trying to update a db table then the update command should do the work.
Eg : UPDATE VBPA3 FROM TABLE DA_XVBPA3U.
Note : The Internal table should be of same structure and should not have duplicate entries.
Regards,
Srini.

How to implement table like structure in MIDP?

I am a starter of midp, and now need to implement something using MIDP 1.0.
I would like to know can I have table like structure in MIDP, just like HTML; or I can only work with List/Form (one dimension display). I can't find related information at api doc come with wireless toolkits

not really knowing what you want to acomplish I have this suggestion: check Mobile Information Device Profile (JSR-37) at http://www.jcp.org/aboutJava/communityprocess/final/jsr037/index.html . This might shed more light on applicable classes/methods/interfaces within MIDP 1.0.

Table-like Data Structure

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