How do you make ADX unions in C# or python code? The UI makes sense in the web portal, but the documentation doesn't seem to make sense for the .net documentation. Maybe I'm just missing something.
using union operator as part of a query isn't affected by which client you use (whether it's the web interface, the .NET/Python client library, etc). you simply need to make sure your query text includes using the operator, and then invoke the query.
Related
I'm writing an API that converts actions performed by a non-technical user into Salesforce.com SOQL 'SELECT', 'UPSERT', and 'DELETE' statements. Is there any resource, library, etc. out there that could validate the syntax of the generated SOQL? I'm the only one at my company with any experience with SOQL, so I'd love to place it into a set of automated tests so that other developers enhancing (or fixing) the SOQL generation algorithm know if it's still functioning properly.
I know one solution here is to just make these integration tests. However, I'd rather avoid that for three reasons:
I'd need to maintain another Salesforce.com account just for tests so we don't go over our API request cap.
We'll end up chasing false positives whenever there are connectivity issues with Salesforce.com.
Those other developers without experience will potentially need to figure out how to clean up the test Salesforce.com instance after DML operation test failures (which really means I'll need to clean up the instance whenever this occurs).
You might solve your problem by using the SoqlBuilder library. It generates SOQL for you and is capable of producing SOQL statements that would be quite error prone to create manually. The syntax is straight forward and I've used it extensively with very few issues.
I found another way to do this.
Salesforce.com posted their SOQL notation in Backus-Noir Form (BNF) here:
http://www.salesforce.com/us/developer/docs/api90/Content/sforce_api_calls_soql_bnf_notation.htm
This means you can use a BNF-aware language recognition tool to parse the SOQL. One of the most common tools, ANTLR, does this and is free. Following the ANTLR example, pass the SOQL grammar into its grammar compiler to get a Lexer and a Parser in your desired language (C#, Java, Python, etc.). Then you can pass the actual SOQL statements you want to validate into the Lexer, and then your Lexer tokens into your Parser, to break apart the SOQL statements. If your Lexer or Parser fails, you have invalid SOQL.
I can't think of a way to do this from outside of Salesforce (and even in Apex I've only got one idea right now that may not work), but I can think of two suggestions that may be of help:
Validate queries by running them, but do them in batches using a custom web service. i.e. write a web service in Apex that can accept up to 100 query strings at once, have it run them and return the results. This would drastically reduce the number of API calls but of course it won't work if you're expecting a trial-and-error type setup in the UI.
Use the metadata API to pull down information on all objects and their fields, and use those to validate that at least the fields in the query are correct. Validating other query syntax should be relatively straight forward, though conditionals may get a little tricky.
You can make use of the salesforce develop nuget packages that leverages SOAP API
I'm using CoreData in my application for DML statements and everything is fine with it.
However I don't want use NSFetchedResultsController for simple queries like getting count of rows, etc.
I've decided to use fmdb, but don't know actual table names to write sql. Entity and table names don't match.
I've even looked inside .sqllite file with TextEdit but no hope :)
FMResultSet *rs = [db getSchema] doesn't return any rows
Maybe there's a better solution to my problem?
Thanks in advance
Core Data prefixes all its SQL names with Z_. Use the SQL command line tools to check out the your persistent store file to see what names it uses.
However, this is a very complicated and fragile solution. The Core Data schema is undocumented and changes without warning because Core Data does not support direct SQL access. You are likely to make error access the store file directly and your solution may break at random when the API is next updated.
The Core Data API provides the functionality you are seeking. IJust use a fetch request that fetches on a specific value using an NSExpressionDescription to perform a function. This allows you to get information like counts, minimums, maximums etc. You can create and use such fetches independent of a NSFetchedResultsController.
The Core Data API is very feature rich. If you find yourself looking outside the API for a data solution, chances are you've missed something in the API.
When is it appropriate to create a helper class for a sql server database using the asp.net framework? Basically I'm trying to create a minature wiki (with multiple pages) and storing all of the data/strings for a specific page into a table on it's own.
Always and Never.
Always, because you want good separation of your data tier from your business logic and presentation tiers (or model and view, or whatever framework you use). Make sure you're thinking of it in these terms, too.
Never, because this is already done for you, on several levels. There are numerous ORMs out there, including Linq-to-sql, NHibernate, Entity Framework, and more. More than that, what is ADO.Net but a set of classes to encapsulate your server?
Well it could be appropriate to return a single instance of a DbConnection object - that way you only specify how to connect to the DB in one spot.
You may find it useful to have a base class for your ADO layer which provides these generic methods to deal with the ADO (part of the .NET framework for connecting to SQL server).
You could have a helper method to populate an object from a DataReader using reflection too.
Also for putting parameters together to send to a SQL command or Stored procedure.
Hope you find this helpful. :)
It's heavily dependant on your project.
For code clarity, and your own sanity, you might find it easier to make a wrapper class for all of your Database manipulation. This way you can have the rest of your code work with native objects, rather than the contents of a DataReader.
Just my advice, but hopefully helpful.
I have used parameterized query number of times I know it helps in preventing SQL injection.
But, I was wondering if I can know what is basic logic working inside a parameterized query
to prevent SQL injection may be it is very simple but I don't know about it. I tried to search google what are the basic of it but every time I found an example that how to use parameterized query in Asp.net.
I know about making a special class which stops those special characters like (',-- etc) which are used in SQL injection, but does stopping only special characters totally prevent SQL injection?
And one last thing does .net parameterized query can fully stop SQL injection?
I think parametrized queries are not dependent on prepared queries database support. Database driver itself passing values the safe way, and how is it done depends on driver itself.
The PostgreSQL manual explains basics about parametrized queries on database level.
On the other hand, parametrized queries simplifies you passing locale sensitive data.
For example, user enters 100,00 decimal, but your server expects 100.00 value.
In every database engine I know, using "prepared" (aka "parametrized", or "static") queries prevents SQL injection. You don't need to filter any characters if they're being passed to parameters. If you ever write SQL that is concatenated together in code rather than prepared with parameters, you are probably at risk for SQL injection. You should the security manual for the database you're using, it will very likely have a section on SQL injection, but just read all of it. I bet it will take under an hour and will give you solid instruction and confidence that you're following best the practices that apply to your database.
It is very simple to retrieve data from a database and display it inside a DataGrid. However, what are the current practices to push the changes in the DataGrid back to the database? One can achieve this by inserting a lot of meta information, however, it is very tedious and not reusable.
There are libraries for persisting data across tiers, but as you say it isn't a simple task. LiveCycle DS ships with this capability when used in conjunction with Hibernate on the server. GraniteDS and Tide can perform a similar function, but for the most part you are left rolling your own. If you are using one of the many MVC frameworks available (I use PureMVC) it isn't difficult to create this type of functionality. Kind of tedious, but not difficult.
Which server side technology would you be using? You need to use HttpServer, WebService or RemoteObject's in Flex to push data to this server side app and that would then update the database.
Unless of course we're talking about a Flex/AIR Desktop App where connecting to databases directly is possible.
You can use RemoteObject, if you have a Java class on the server side that takes care of database connection and provides method to update database.
Just Create an ArrayCollection object from modified datagrid and pass it while doing a method call.
I think making changes to the database is the easiest part of this whole thing. The hardest part is making the DataGrid know exactly from which database table each cell comes from. If you're the one writing the query, then you can probably return a lot of meta-data, such as the private key and table name for each cell.