I understood we can read data from a table using command in Schema crawler.
How to do that programatically in java. I could see example to read schema , table etc. But how to get data?
Thanks in advance.
SchemaCrawler allows you to obtain database metadata, including result set metadata. Standard JDBC provides you a way to get data by using java.sql.ResultSet, and you can use SchemaCrawler for obtainting result set metadata using schemacrawler.utility.SchemaCrawlerUtility.getResultColumns(ResultSet).
Sualeh Fatehi, SchemaCrawler
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I am able to read hive external table using spark-shell but, when I try to read data from hive managed table it only shows column names.
Please find queries here:
Could you please try using database name as well along with table name?
sql(select * from db_name.test_managed)
If still result is same, request you to please share output of describe formatted for both the tables.
I am trying to build a chatbot in Rasa/Dialogflow, the problem i ham facing is to convert English to SQL query so that what user write in English can be converted into SQL fetch data from MYSQL database and display result to use.
Can someone suggest me how to do it?
Ideally this is only possible through solutions like SEQ2SQL(Link here for reference).
But I implemented it in a workaround fashion:-
I got the json using tracker.latest_message .
After which I processed the json to make our own structured json like:
[{'column_name':'a',
'operator': '=',
'value':'100'},
{'column_name':'b',
'operator': '>',
'value':'100'}]
Above structure was used to form the where clause of the query.
Same way I made a custom json for Select Part as well :-
[{sum:column1},{count:column2}]
5.Then I looped through the json I had created and made our queries.
Note:- This json Structure will not be able to cover all possible scenarios but worked decently for me.
Is there an equivalent of SHOW CREATE SCHEMA in presto? I just want to see the value of the location field.
Presto do not support SHOW CREATE SCHEMA. It only supports SHOW CREATE option for VIEW and TABLE.
I am trying to insert XML data into Cassandra DB. Please can somebody suggest the flow in nifi. I have JMS on which I need to post messagedata and then consume & insert the data into Cassandra.
I'm not sure if you can directly ingest XML into Cassandra. However you could convert the XML to JSON using the TransformXml processor (and this XSLT), or as of NiFi 1.2.0, you can use ConvertRecord by specifying the input and output schemas.
If there are multiple XML records per flow file and you need one CQL statement per record, you may need SplitJson or SplitRecord after the XML-to-JSON conversion has taken place.
Then you can use ReplaceText to form a CQL statement to insert the JSON, then PutCassandraQL to push to Cassandra. Alternatively you can use CQL map syntax to insert into a map field, etc.
My question is pretty simple. I am working on Kentico 9 with its SQL Server database which contains several tables which had been added directly from the SQL Management Studio by an external contractor. The fact is that those tables are being used to store custom content which will be displayed for a site, but, in the code they don't have the code for making queries. I mean, they don't have Info and Provider classes.
https://docs.kentico.com/display/K82/Retrieving+database+data+using+ObjectQuery+API
According with this, all tables into the Kentico database can be accessed by invoking methods on these classes, but I don't have it this time.
Something like this, it will not work if I use my table name:
var user = UserInfoProvider.GetUserInfo("administrator");
var items = CustomTableItemProvider.GetItems("MyTable")
.TopN(10)
.WhereEquals("ItemCreatedBy", user.UserID)
.OrderBy("ItemCreatedWhen");
My question is:
can I query any table by its name?
One last thing:
I cannot declared those table as "custom table" because it seems to be a bug in the CMS.
Or you can pull data using your own SQL query:
var ds = ConnectionHelper.ExecuteQuery("select ....", null, QueryTypeEnum.SQLQuery);
Nevertheless I would recommend to create a custom class inside a custom module (much more robust than custom tables) instead and use the generated Info and InfoProvider classes to get and manipulate data.
I think an object has to be registered within the system (created through Kentico UI or API) in order to be pulled from DB with object query.
So I'd choose one of the following options:
Use Entity Framework or something similar to work with that data
Create appropriate custom tables or even custom module and push data there. Not sure why you can't create a custom table... What is an error you're getting?
If you need to present data on the UI only (without processing on the back end) - use just custom queries
Hope this helps.
If you are accessing in code then you could do it the good old fashioned way. If you want to pull data from the database to display on the website you could also do so by creating a custom query and using a transformation to display the fields, then use a repeater on the page to display the transformed data. Alternatively you can use a SQL datasource with a basic repeater, but you still have to create a transformation to display the data. Both methods allow you to access the data in the tables from within the CMS UI, no need to touch any code behind.
If your objective is to read data from these database tables to transform on webpage e.g. using CMS Repeater webpart, you can simply create custom query(s) in Kentico itself and load data using it. You can find the detail here on how to create custom custom queries and load data using it.
On the other hand you can also write your custom classes and define the custom methods where you can pull data using your own SQL query like this:
var ds = ConnectionHelper.ExecuteQuery("select ....", null, QueryTypeEnum.SQLQuery);
Lastly I don't think there should be any issue to create custom table instead of those direct DB tables, only thing we have to ensure code name of custom table should be unique means don't try to use exact same name because it'll cause exception due to same table name already exist in DB. You can please share exception you getting while creating custom table so that I can help you out further.