I'm trying to build a database but i'm struggling with the type of some data.
Basicly i would like to have something that behave like a combobox : you have several choices but can only choose one.
Unfortunatly i can't define that in a sql database.
I came up with the idea to store all the different "choices" in a table and each entries will fill one, leaving 10+ empty field.
Isn't there another method to do this in a cleaner way ?
Enumerated types behave as you describe.
Related
In several notes applications, instead of handling related data as separate documents, if the size of the data is small (less than the 32k limit), I'll make several multi valued fields and display it in what I call a "List Panel". It's a table where each column displays one multi-value field. Since fielda(1) goes with fieldb(1) that goes with fieldc(1) there is a concept of rows. (I did a similar thing in my auditing routine discussed here )
It is always assumed that each field has exactly the same number of elements.
All the multi-value fields are then stored on the single document. This avoids several coding conventions that made my eyes bleed like having date changed, who changed it, new value fields for each field we wanted to audit. Another thing that this kept to a minimum was having to provide multiple fields for the same thing that locked you into a limit. Taxrate1, Taxrate2, Taxrate3, etc...
In my "Listpanel" the first column is a vertical checkbox. (One for each element in my lists) This is so I can select one item to bring up and edit, or select multiple values to delete "rows" or apply some kind of mass change to them.
What would be the best way to handle this under xPages to get this functionality? I tried making a table but am having the devil of a time to get the checkboxes to line up with their corresponding data items.
Views and dojo-grids seem to assume we're using a document for each row.....
This TableWalker may provide what you want http://www-10.lotus.com/ldd/ddwiki.nsf/dx/Tutorial-Introduction-to-XPages-Exercise-23
It was created when XPages was all very new, so it's SSJS rather than Java. But if you're comfortable wiith Java, converting it probably won't be a challenge.
You could use a repeat control to display the values and build a table using the table row tags in the repeat. You would want to calculate the id of the checkbox to be able to take an action on that selected row. The repeat var would be just one of your multi-value fields and you use the index of the repeat to get the value for that row from the other multi-value fields.
I have problems with my records within my database, so I have a template with about 260,000 records and for each record they have 3 identification columns to determine what time period the record is from and location: one for year, one for month, and one for region. Then the information for identifying the specific item is TagName, and Description. The Problem I am having is when someone entered data into this database they entered different description for the same device, I know this because the tag name is the same. Can I write code that will go through the data base find the items with the same tag name and use one of the descriptions to replace the ones that are different to have a more uniform database. Also some devices do not have tag names so we would want to avoid the "" Case.
Also moving forward into the future I have added more columns to the database to allow for more information to be retrieved, is there a way that I can back fill the data to older records once I know that they have the same tag name and Description once the database is cleaned up? Thanks in advance for the information it is much appreciated.
I assume that this will have to be done with VBA of some sort to modify records by looking for the first record with that description and using a variable to assign that description to all the other items with the same tag name? I just am not sure of the correct VBA syntax to go about this. I assume a similar method would be used for the backfilling process?
Your question is rather broad and multifaceted, so I'll answer key parts in steps:
The Problem I am having is when someone entered data into this
database they entered different description for the same device, I
know this because the tag name is the same.
While you could fix up those inconsistencies easily enough with a bit of SQL code, it would be better to avoid those inconsistencies being possible in the first place:
Create a new table, let's call it 'Tags', with TagName and TagDescription fields, and with TagName set as the primary key. Ensure both fields have their Required setting to True and Allow Zero Length to False.
Populate this new table with all possible tags - you can do this with a one-off 'append query' in Access jargon (INSERT INTO statement in SQL).
Delete the tag description column from the main table.
Go into the Relationships view and add a one-to-many relation between the two tables, linking the TagName field in the main table to the TagName field in the Tags table.
As required, create a query that aggregates data from the two tables.
Also some devices do not have tag names so we would want to avoid the
"" Case.
In Access, the concept of an empty string ("") is different from the concept of a true blank or 'null'. As such, it would be a good idea to replace all empty strings (if there are any) with nulls -
UPDATE MyTable SET TagName = Null WHERE TagName = '';
You can then set the TagName field's Allow Zero Length property to False in the table designer.
Also moving forward into the future I have added more columns to the
database to allow for more information to be retrieved
Think less in terms of more columns than more tables.
I assume that this will have to be done with VBA of some sort to modify records
Either VBA, SQL, or the Access query designers (which create SQL code behind the scenes). In terms of being able to crunch through data the quickest, SQL is best, though pure VBA (and in particular, using the DAO object library) can be easier to understand and follow.
Actually I have a new client & their Database has no standard naming conventions & the application is in classic asp.I have a form in which a form there are many values in the different textboxes, it it very difficult to trace the value come from which table.& also there is no erd.
I need a query from which I can get the table name with column name by giving Value.
Let's suppose I have a value having label name abc#= '6599912268'
& the new project has no ERD no standard of naming conventions... I need a fast way to know the abc# ='6599912268' is taking from which table & which column name.... like this the UI has many values which is time taken to trace manually
Is there any way to trace it?
The simple answer is no. There is no way to trace table/column it comes from by mere inspection of the value.
I suggest the following.
Find out what type of db your product is using. Where it is situatede, do you have access to it.
If you have access to the database, get to know the db structure. What each table is meant to store, the relationships etc. Speak to the db administrator or the business analayst to increase your knowledge on the product domain.
Once you have the db structure, try and compare the table to the page. Eg. The user details will most like be stored in a db table named 'Users' or 'Membership' Catch my drift?
Then have a look at the web sites source code. Look at the specific page you are at. Is the sql code embedded in the source code (asp page) or does it call a COM server or something similar? If you are "lucky" (and I say lucky for on the purpose of your problem that you are having) you fill find the sql code in the asp page.
If it calls a COM object or something similar, then you will have to dig up the source code for that, and that is most likely where you sql will reside.
There is no easy way to do this, you have to use a stored procedure to loop over all the tables in the database and search for the value, and it will probably take a while.
There's a stored procedure and examples here: Search all columns in all the tables in a database for a specific value. You'll see there are stored procedures for finding dates, strings, numbers.
Not possible, and If you search the column with the value, there is a possible chance that you get multiple columns with the same value, so how would you differentiate them and the same case is for the table.
I want to sort information in a dojo EnhancedGrid (connected to database through JsonRestStore). I know dojo grids provide functionality to sort based on a single column. However, in my grid, one column contains combined information from multiple fields (e.g., last name, first name, email, age) of database table. Is there a simple way to sort the grid or the data in the store based on a single filed in database table (e.g., last name)?
It seems I can use "query" to change the view of the store (grid is a view of the store if I understand correctly), but I don't understand how to write a query to do that. Can anyone give me more information about the syntax of using query or how to solve this issue?
Thank you!
It looks like you have to use what is called a comparatorMap for customized grid sorting.
here's one example :
http://www.ibm.com/developerworks/web/library/wa-aj-dojogrid/index.html
(look for the section 'Listing 15. Customize the sort function of Dojo
Grid')
inside the comparator map function is where you would convert the strings to
numbers and make the numeric comparison.
I've been tasked with learning Lotus Domino Designer - not sure what I did in a previous life, but it must have been pretty bad... - and was wondering how to do a lookup on a database to get some values for selections. As this information could potentially be used in a lot of the applications, I'd prefer it only to be in the one place.
I gather I can use #DBColumn, but what happens if an entry in that lookup changes? If the unique value of the lookup is the text, then the relationship would be broken, wouldn't it? Is there any way of mimicing the idea of relational lookups?
I'm assuming I'm looking at Lotus development from the wrong angle, as this seems to be a real limitation of look ups.
I haven't found any decent learning material on the interwebs, so would appreciate any help.
Ta
You would want to store a unique ID along with the textual value in the source database (not unlike what you would do in an RDBMS). Then, only store that ID in any referencing documents, and use a computed-for-display field to lookup the display value. (There is a performance consideration here - and you could "de-normalize" the data and store the ID and text value in the referencing documents, and do some asynchronous work to keep the values in sync - eg: using a scheduled agent that runs every night or every week).
If DB1 has the key values and DB2 has the documents which will reference these values, then in the form in DB2, you would still do a #DbColumn to lookup your value list. In the lookup view in DB1, concat the text value and ID with a pipe separator (textField + "|" + ID) in the first column. That will tell Notes to store only the ID value (what follows the pipe is the "alias" and is what will be stored).
Note: I would avoid using #DocumentUniqueID as the unique ID for these values, as the Document Unique ID will change if the documents are copied and pasted, or the entire database is copied, etc. You can use the #unique formula function in a computed-when-composed field to generate something close to a unique ID (almost like an identity column in sql).
If you need relational properties, look for non-Notes solutions. It is possible to get some relational behavior using document UNIDs and update agents, but it will be harder than with a proper relational backend.
Your specific problem with referencing to a piece of text that might change can to some extent be resolved by using aliases in the choice fields. If a dialog list contains values on the form...
Foo|id1
Bar|id2
...the form will display Foo but the back-end document will store the value id1 - (and this is what you will be able to show in standard views - although xpages could solve that). Using the #DocumentUniqueID for alias can be a good idea under some circumstances.
It depends on where your using the data. The #DBLookup or #DBColumn will work in Lotus Notes fields if the fields are set to be computed for display. That way they always get the most up to date information when you open the form etc.
If you make it so the data is saved on to the document then you will have to write some update code when you need to refresh the values.
The Lotus Notes help files for designer are pretty good, have a look at that.
SM
You could use a key or alias to store the relationship to your lookup value so if the value itself changes, the connection remains because the alias is intact. For example, if your lookup values were being stored as a collection of documents, I'd have the #DBColumn retrieve Document UNID|lookup value pairs. When in display mode, you could then retrive the value using #GetDocField. If the lookup values are in a different database, then you'd have to retrieve them for display using #DBLookup and construct a view that is keyed off of the UNID or whatever key you decide to use.The only drawback to this technique is that you wouldn't be able to display the field value in views as the actual value isn't stored in the document, just a reference to it. Using XPages, though, you COULD map the relationship into a dynamic datatable just like you would in a truly relational system.
It's tricky, but using LEI, you could also use Notes to front-end a relational backend system, also giving you the dynamic relationship you desire in your lookups.
Hope this helps!
The content of the lookup can change freely. A problem only arises (as it would on any other platform in the same circumstances) if the lookup key changes. You need to use a key that won't change. Human-readable text is an advantage, but if you want to be able to change your key description from, say, "Divisions" to "Business Units" and still have lookups work, you need to use an alias of some kind, which will presumably be mapped to your text description and only used internally. #Unique is pretty good for this, and gives a shortish key, if that is important to you. #DocumentUniqueID is most reliable, but as Ed pointed out, will change (must change - it's a new document) if you copy/paste or make a non-replica copy. This is easy to get around, though. Create a Computed-when-composed field (called, say, "LookupRef") on the form you are using for your reference document with the formula "#DocumentUniqueID". That will capture the ID at the time of creation, and it will not change on copy/paste etc. Use that as your key.