In my Mongo DB, I have a user ID and status fields. Before inserting a new record I've to check for some combination of these fields and insert a new record accordingly.
In NodeJS with Mongoose, 'pre' is a functionality where I can validate before inserting and proceeding accordingly. My current environment is Ktor, my programming language is Kotlin, and the framework I'm using to interact with Mongo is KMongo.
Is there an equivalent of 'pre' in KMongo?
Related
I have an upgrade wizard (TYPO3 11) which changes the data of a table.
This is done with the querybuilder:
$queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)
->getQueryBuilderForTable('tt_content');
$queryBuilder
->update('tt_content')
->set('CType', 'newCType')
->where($queryBuilder
->expr()
->eq('CType',$queryBuilder->createNamedParameter('oldCType')))
->execute();
But I also need to rename a field in a table:
ALTER TABLE tt_content RENAME COLUMN tx_myext_old_field TO tx_myext_new_field;
I can't find any documentation or example of doing this with the querybuilder.
The normal way woult be to provide a ext_tables.sql in your extension. This is read by TYPO3 to build a virtual "database scheme" how it should look.
The database schema analyser will than provide the information, and database alteration are suggested.
You could add a database must be up to date constraint to your upgrade wizard, that way it is ensured that the field is changed.
DTL is a special task, and you have to provide the correspinng queries yourself ... which are different for different dbms systems. So using the normal way would be recommended.
The platform/driver may have some generig helper methods providing some native sql parts for doing stuffs like that. The may be possible to provide custom stuff based on SchemaMigrator or SchemaManger etc - but thats low-level stuff.
doctrine/dbal directly do not really provide these DTL as API. And the querybuilder is not meant to be used for that low level stuff at all. That's the wrong tool for such tasks.
You can also change columns of core tables that way, by providing simply the table name and the column defintion only for the field you want to change.
The official way is to handle this with ext_tables.sql and the database schema analyser.
See: https://docs.typo3.org/m/typo3/reference-coreapi/main/en-us/ExtensionArchitecture/FileStructure/ExtTablesSql.html
The concept of renaming a column could not work:
On installing the extension all new fields are generated (or should be generated if in composer mode). And as the extension should work with the new columns they are already defined.
And before the upgrade wizard could rename a column these columns are existent already which prevents a rename.
In the end I do a content copy enhancing the update query like this:
$queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)
->getQueryBuilderForTable('tt_content');
$queryBuilder
->update('tt_content')
->set('CType', 'newCType')
->set('tx_myext_newfield1',$queryBuilder->quoteIdentifier('tx_myext_oldfield1'),false)
->set('tx_myext_newfield2',$queryBuilder->quoteIdentifier('tx_myext_oldfield2'),false)
->where($queryBuilder
->expr()
->eq('CType',$queryBuilder->createNamedParameter('oldCType')))
->executeStatement();
I am using Thingworx Platform for IoT. I have connected Thingworx and SQL. I have created 2 database SQL services of the type query and command. Also I have created two tables named Temperature and Humidity.
I am getting Temperature and Humidity values in Thingworx platform. But I am unable to send it to the database, can anyone help? How can I call the properties in the command service?
Database.Conf sql Command code
insert into INFO(Temperature)
values ([[]]);
Thing-Test Subscription Code
var params={Temp:me.Temp_Prop,Hum:me.Hum_Prop};
var result=Things["DatabaseConf"].InsertRecords(params);
When you create a service in ThingWorx you can select the type: "query" is a valid option when you have to insert or retrieve values from a database. You can test the query on SQl and copy/paste into the service.
Check if the thing that connects you to the DataBase has the property "isConnected" equal to True.
Maybe you should also think about how to trigger the Insert service, you can use ValueChange triggers or a Periodic Trigger.
You need an additionnal service of type javascript where you can retrieve the properties, using me.property and invoke the sql services. You can add input parameters to the sql services and use them like this: [[inputParameter]]. In your example that should look like:
insert into INFO(Temperature)
values ([[temp]],[[Hum]]);
If you use the arrow on the right of your input parameter, ThingWorx will write it for you in the proper way already.
Is there an easy way to determine or find the underlying SQL field type of a Django Field, for any of the supported by default database backends? I have searched on the web and there is no documentation over how the Django fields are represented in SQL in each of the supported databases. The only way for me to see the underlying SQL field type, is to run the mysqlmigrate command of manage.py and examine the SQL code.
The type depends on the database backend, so you need to get a db connection first:
from django.db import connection
and now you can look up the field via the model Meta API:
my_field = MyModel._meta.get_field('my_field_name')
and use its db_type method:
my_field.db_type(connection)
which will return something like "varchar(10)".
Be sure you really need to do this, though. Usually this information is only useful inside migrations.
I'm a complete and total newb at SQL. I know how to correlate data between tables, but that's pretty much it (and then, only if I have GUI...). I am attempting to write some automated tests for a site we are working on.
The project I'm working on contains 2 schema for users that register to the site. From time to time, we use the other, for "private" users. When they register, the users that go to the "private" site also go in the second schema.
Basically, during the writing of my tests, whenever I need a registration token from the default schema, I use this SQL command in my tests (which I write using Java code):
select tokenValue from Tokens where TypeOfToken = 'REGISTRATION' and user_id = '48'
This works without problems, since the default schema is already specified elsewhere.
Is there a way for me to specify from which schema I need to select the token from?
Thank you.
select tokenValue from [Insert Schema here without brackets].Tokens where TypeOfToken = 'REGISTRATION' and user_id = '48'
I've been reading the documentation, but I couldn't find any information about it.
Is it possible to have Hibernate send user-provided SQL queries in order to UPDATE or to INSERT an object in the database?
In other words, is it possible to have session.saveOrUpdate( myObject ); , which generates update mySchema.myObject set field1=?, field2=?, field3=? where unique_key=?
to be replaced with a manual query from a user-provided String?
This is well described in the reference documentation. There are caveats, though : the session and the second-level cache aren't aware of the changes made to the entities, the version field is not updated, etc.
And if HQL is still not sufficient, you may always fall back to SQL queries.