I am using popoto.js and try to query my database like this:
MATCH (t1:Tag)-[l:EXPERT_LINKED_TO]->(t2:Tag) RETURN t1, l, t2
Problem is, that I can only query in popoto.js with a WHERE-clause. So I have to choose a specific Tag for querying the DB.
But I want to get all Tags who are in a relationship with other tags without to specify a property.
So is there a way to query the DB without setting a property in popoto.js?
Related
I'm having a lot of trouble trying to update a single (record) object in my database.
context['eval_list'] = Evaluering.objects.update(eval_relationer_id=self.kwargs.get('pk'))
I use objects.update, but it updates ALL my objects fk. How do I achieve only updating one object? I have also tried this:
context['eval_list'] = Evaluering.objects.update_or_create(eval_relationer_id=self.kwargs.get('pk'))
But this creates a new object and does not update the record that I want to update. I know why it creates a new objects, and it is because the FK I'm trying to update is null. Surely, there must be a way to only update and not create a single record? What am I missing here?
I tried adding a filter, but it feels redundant? I tried this:
context['eval_list'] = Evaluering.objects.filter(eval_relationer_id=self.kwargs.get('pk')).update(eval_relationer_id=self.kwargs.get('pk'))
I did consider trying to create an ID of the FK instantly and not later on, but I couldn't really get that to work, but if I created an ID then the update_or_create would work because an ID would exist already, BUT I cannot believe that I can't update a single object without create?
If creating the ID earlier on is the only work around, I will have to figure out how.
MyModel.objects.filter(pk=some_value).update(field1='some value')
The filter gets your object (returns the Queryset with only that object), then the update changes some other field that is not the PK to whatever you want.
In your case probably something like this:
context['eval_list'] = Evaluering.objects.filter(eval_relationer_id=self.kwargs.get('pk')).update(some_attribute='some value')
After help from #Hanny I've figured out was going wrong.
I was trying to filter by the eval_relationer_id, when I should have been filtering by the evaluation pk and getting that specific PK. Otherwise I would be updating ALL the values which is not what I wanted.
So by filtering by pk:
filter(pk=self.kwargs.get('pk'))
And updating by the attribute / fk that I want to update
update(eval_relationer_id=self.kwargs.get('pk'))
This is the end-result:
context['eval_list'] = Evaluering.objects.filter(pk=self.kwargs.get('pk')).update(eval_relationer_id=self.kwargs.get('pk'))
In a recipe database I have two tables. One has the ingredients of every recipe [Recipe_ingr] and the other the available measures and weight for every ingredient [Weight2].
When I input a new ingredient for a recipe, I would like to be able to choose the available units for only that specific food.
I have tried with this expression in the control field but it prompts me to choose first, and then the options remain the same for all the records, not changing dinamically according to the record ingredient code.
SELECT [Weight2].[Msre_Desc], [Weight2].[Gm_Wgt] FROM Weight2 WHERE Weight2.NDB_No Like Recipe_Ingr.NDB_No ORDER BY [Msre_Desc], [Gm_Wgt];
Picture of my tables
Update:
I tried the syntax change suggested by June9 but still the control doesn't update automatically with every record as you can see in this picture: Table
Suggest you name controls different from fields they are bound to, like tbxNDB. The SQL needs to reference a field or control that is on the form. Also, LIKE operator without wildcard accomplishes nothing that an = sign wouldn't. Also recommend not using exactly same name for fields in multiple tables.
If you use that SQL statement in combobox RowSource, try:
SELECT Msre_Desc, Gm_Wgt FROM Weight2 WHERE NDB_No = [tbxNDB] ORDER BY Msre_Desc, Gm_Wgt;
You want to save Msre_Desc as foreign key, not a record id generated by autonumber?
I read about createCriteria, and kind of interested on how these works, and its usability in providing values for dropdown box.
So say, i have a table in the database, Resource table, where i have defined the table in the domain class called Resource.groovy. Resource table has a total of 10 columns, where 5 of it are
Material Id
Material description
Resource
Resource Id
Product Code
So using the createCriteria, and i can use just like a query to return the items that i want to
def resList = Resource.createCriteria().list {
and {
eq('resource', resourceInstance)
ne('materialId', '-')
}
}
Where in the above, i want to get the data that matches the resource = resourceInstance, and none of the materialId is equal to '-'.
I want to use the returned data from createCriteria above on my form, where i want to use some of the column on my select dropdown. Below is the code i used for my select dropdown.
<g:select id="resourceId" name="resourceId"
from="${resList}"
disabled="${actionName != 'show' ? false : true}" />
How do i make it so that in a dropdown, it only shows the values taken from column Product Code? I believe the list created using createCriteria returns all 10 columns based on the createCriteria's specification. But i only want to use the Product Column values on my dropdown.
How do i customize the data if in one of the select dropdown in my form, i wanted to show the values as "Resource Id - Resource Description"? The values are combination of more than 1 columns for one select dropdown but i don't know how to combine both in a single select dropdown.
I read that hql and GORM query are better ways of fetching data from table than using createCriteria. Is this true?
Thanks
First of all refer to the document for using select in Grails. To answer all questions:
Yes, the list to select from in the dropdown can be customized. In this case it should be something like from="${resList*.productCode}"
Yes, this can be customized as well with something like
from="${resList.collect { \"${it.resourceId} - ${it.resourceDesc}\" } }"
It depends. If there are associations involved in a domain then using Criteria will lead to eager fetches which might not be required. But with HQL one gets the flexibility of tailoring the query as needed. With latest version of Grails those boundries are minimized a lot. Usage of DetachedCriteria, where queries etc are recommended whereever possible. So it is kind of mixing and matching to the scenario under consideration.
.Hi i'm working with Asp and SQL-Server and i have no problem with writing dynamic query
I'm trying to Write a search page for searching people.
I have 3 related tables:
See my table diagram in : http://tinypic.com/r/21159go/5
What i'm trying to do is to design a search page that a person can search users with a dynamic number of attributes.
Example:
think that a username called "User1" has 3 attributes named "Attr1", "Attr2" and "Attr3" related to him in "UserAttributes" table and "User2" has 3 attributes named "Attr1", "Attr2" and "Attr4".
Attribute names and other bunch of items unrelated to search function saved in "Attributes" Table. This is because i want to relate an attribute between multiple users. and their values are stored in "UserAttributes" table.
Well someone wants to search upon "Attr1" and "Attr2" and wants to return all users that have "Attr1" and "Attr2" with specific value.
I need a query to know how to implement this. I can write a dynamic query with asp.net so if someone please give me a query for this one example i have brought, i would be thankful
P.S. This is not my real database. my real database is much more complex and has more fields and tables but i just cut it and brought only necessary items. and because attributes are very dynamic they can't be embedded in table columns.
Thanks in advance
Based on your DB diagram your code would be something like this
update:
SELECT u.*
FROM users AS u
LEFT OUTER JOIN UserAttributes AS ua1
ON u.USER_ID = ua1.USER_ID
LEFT OUTER JOIN UserAttributes AS ua2
ON u.USER_ID = ua2.USER_ID
WHERE (
ua1.attribute_id = 'att1'
AND ua.attribute_value = 'MyValue' )
AND (
ua2.attribute_id = 'att2'
AND ua.attribute_value = 'MyValue2' )
In where clause you would specify the attirbute_Id and what value you are expecting out of it. Than just decide if you want to restrict users to have all values match or just one of them, in that case modify AND between statements to be OR
if you just want to do this quick and dirty you can create your own class library that can create adhoc sql that will pass to the database.
if you want more organized matter, create SP that will bring back users and accepts any left of id and value. Do a lot of that by passing list separated by comma, colon or semicolon. Than split it up in SP and filter results based on those values
there are many other alternatives like EntityFramework, LINQ-to-SQL and other options, just need to figure out what works best for you, how much time you want to spend on it and how easy will it be to support later.
So, another in my series of Kohana 3 ORM questions :)
I have, essentially, a pivot table, called connections. The connections table connects a song to a keyword. That's all great and working (thanks to my last two questions!)
I want to output the most connected songs by keyword. So, to somehow query my connections table and output an object (with an arbitrarily limited number of iterations $n) that ranks songs by the number of times they have been connected, ie. the number of times that particular song_id appears for that particular keyword_id.
I have literally no idea how to achieve this, without querying every single row (!!!) and then counting those individual results in an array.... There must be a more elegant way to achieve this?
I believe this is more of an SQL question. Using the DB query builder:
DB::select('songs.*')->select(array('COUNT("keywords.id")', 'nconnections'))
->from('songs')
->join('connections', 'LEFT')->on('connections.song_id', '=', 'songs.id')
->join('keywords', 'LEFT')->on('connections.keyword_id', '=', 'keywords.id')
->group_by('songs.id')
->order_by('nconnections')
->as_object('Model_Song')
->execute();
or in SQL
SELECT `songs`.*, COUNT(`keywords`.`id`) AS `nconnections` FROM songs
LEFT JOIN `connections` ON `connections`.`song_id` = `songs`.`id`
LEFT JOIN `keywords` ON `connections`.`keyword_id` = `keywords`.`id`
GROUP BY `songs`.`id` ORDER BY `nconnections`
should return the result you want.
You'll want to have an accessible property called nconnections in your song model. The simplest way to do that is to add a public member so you don't tamper with ORM's inner workings.
I'm assuming you're using a model called 'Song', linked to a 'songs' table, a 'Keyword' model linked to a 'keywords' table and in the 'connections' table foreign keys 'song_id' and 'keyword_id' for each model respectively.