I am developing an application. In that I want to create an XML file with sqlite data and place another XML data into sqlite field. So please tell me how to do this.
Well hope you used Core Data to interact with your DB.
If you did so, just loop your Entities and use a NSMutableString to build your XML document.
Related
I'm using my app to import some PDF files.
But I'm trying to insert my PDF file int my database. I'm using Core Data. Is it possible to do this ? If it is, how can I do it ? Which kind of types I have to use (NSData, NSDocument, ... ?)
Thanks you so much! :)
To store a PDF (or really any big data blob):
Use the Core Data "binary" type for the attribute, which corresponds to NSData.
In your Core Data model, turn on "Allows External Storage" for the attribute so that Core Data can store the data outside of the persistent store.
It's often better to just write the PDF to a file, and store the filename in your persistent store instead of the whole file.
Usually for large files, i.e large images or pdf files, what you should save in core data is simply a reference to the file, and store the pdf in NSCachesDirectory or in a permanent directory, depending on your needs.
Hope that helps.
Currently I am working with the project in which I need to parse complex XML, which contains multilevel details (Name & Paths for PDFs, PNGs, etc) at each node.
I need to store all the data in local memory of iPhone/iPad.
Should I create classes for each of those details and make appropriate tables in SQLite or store the data as BLOB and retrieve all the data all the time?
Any Suggestions, thoughts are most welcome...
EDIT:
I am storing Files in DocumentsDirectory and path to SQLite database. Question is to create well defined database tables or to store data in BLOB form.
Pros and Cons for both approach would be much appreciated. Thanks.
in my opinion you should simply use BLOB : when you startup your app load you'r xml into an object all changes will be made to that object so you can win the time to rewrite back to disk
on exit application save all to disk..
Using of BLOB is not a good process .Store all pdf and images in Document directory..store that path only in DB...
I have a SQLite database. Should I put the DB in a data structure with Core Data. How can I do? My problem is "z relations" between tables.
It's possible?
Core Data isn't SQL even when it employs an SQLite store. Although it is theoretically possible to convert a standard SQLite file to the schema Core Data uses, that is difficult and risky especially given that Apple doesn't document the schema and can therefore change it without warning. You really need to translate the SQL data into Core Data objects.
The best way is to write a utility app containing you Core Data model. Read in the SQL data with the standard functions and then use that data and relationships to create the appropriate managed objects and object relationships in Core Data.
Usually you have code anyway for creating managed objects, populating attributes and setting relationships. Just use that code but instead of providing the data from the UI or a feed, provide it from the data provided by SQL.
I found a solution. In the future, should I use SQLite directly, but for those who have a similar problem to mine this solution works well.
Step 1: Core Data in your table add column headed gl'ID temporary relations of the original table.
Step 2: In the data in CSV add two columns. The first column contains the value 1 and refers to P_OPT of Core Data and the second column contains the identifier of the table and retrieved P_ENT generated by reading the SQLite Core Data in the table Z_PRIMARYKEY.
Step 3: With any editor Mac transfer your data in SQLite files generated by Core Data. Remember to attach gl'ID (relations) in the temporary columns.
Step 4: Through the use of the SQL UPDATE command (works with any SQL editor on the Mac) updates all ID columns of relations in Core Data with the value Z_PK. The value retrieved by the queries and the use of temporary columns.
Sorry for the bad English. I hope not to have been convoluted with the explanation and useful to others.
I am developing an app where I need to insert data coming from web service into sqlite3 database.Web service returns XML data with 5 tags.Now after XML parsing how to insert parsed data into sql database?
Can I code for this???
Thanks in advance..
Inserting XML data in sqlite database is no different that inserting any data. So there are 3 parts of the problem you are trying to solve:
Calling the web service and getting the data
Parsing the data and populating some object
Inserting that data in sqlite database which has columns as per your object structure
NSURLConnection and NSXMLParser are the classed you need to look at for solving first 2 problems. Third one would be solved using sqlite library. Without more information about object structure it is difficult to suggest anything else. But you should find enough documentation on using sqlite if you search around.
I have a CSV file containing data.
I want to load it into a Core Data managed sqlite db.
I just ran one of the sample Core Data Xcode apps and noticed it created the db file.
I noticed table names all started with Z and the primary keys were stored in separate table so from this am I right in presuming that just importing the CSV data directly into the db using sqlite3 command line might mess up primary keys.
Do I need to write a program to read in the CSV line by line and then create objects for each row and persist them to the db.
Anyone got any code for this?
And can I write a desktop client to do this using Core Data. If so will the db be fine to use in IPhone core data app?
Can I then just include the prefilled db in my project and it will be deployed with the app correctly or is there something else I should do.
Use NSScanner to read your CSV file into the NSManagedObject instances in your Core Data store.
I have some categories on NSString for reading and writing CSV files from/to NSArrays. I'll post them online and edit my answer with a link to it.
edit
They're online here: http://github.com/davedelong/CHCSVParser