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How to find out client ID of component for ajax update/render? Cannot find component with expression
The following code is inspired from PrimeFaces DataGrid + DataTable Tutorials and put into a <p:tab> of a <p:tabView> residing in a <p:layoutUnit> of a <p:layout> . Here is the inner part of the code (starting from p:tab component); the outer part is trivial.
...
Rails find_or_create_by more than one attribute?
...ibutes can be connected with an and:
GroupMember.find_or_create_by_member_id_and_group_id(4, 7)
(use find_or_initialize_by if you don't want to save the record right away)
Edit: The above method is deprecated in Rails 4. The new way to do it will be:
GroupMember.where(:member_id => 4, :group...
Postgres unique constraint vs index
...
I had some doubts about this basic but important issue, so I decided to learn by example.
Let's create test table master with two columns, con_id with unique constraint and ind_id indexed by unique index.
create table master (
con_id integer unique,
ind_id integer
);
create uniq...
What is the standard naming convention for html/css ids and classes?
...sing it a lot. For example, if you've got your underscore key on the underside of the keyboard (unlikely, but entirely possible), then stick to hyphens. Just go with what is best for yourself. Additionally, all 3 of these conventions are easily readable. If you're working in a team, remember to keep...
How to check if a user likes my Facebook Page or URL using Facebook's API
...works if the user has granted an extended permission for that which is not ideal.
Here's another approach.
In a nutshell, if you turn on the OAuth 2.0 for Canvas advanced option, Facebook will send a $_REQUEST['signed_request'] along with every page requested within your tab app. If you parse that...
Can I use CASE statement in a JOIN condition?
...T *
FROM sys.indexes i
JOIN sys.partitions p
ON i.index_id = p.index_id
JOIN sys.allocation_units a
ON CASE
WHEN a.type IN (1, 3) AND a.container_id = p.hobt_id THEN 1
WHEN a.type IN (2) AND a.container_id = p.partition_id THEN 1
EL...
Get generated id after insert
I'm using the SQLite with Android, and I want to know the best way to get the generated id of the row I inserted.
5 Answers...
SQL “select where not in subquery” returns no results
...L:
SELECT *
FROM common
LEFT JOIN
table1 t1
ON t1.common_id = common.common_id
WHERE t1.common_id IS NULL
NOT EXISTS:
SELECT *
FROM common
WHERE NOT EXISTS
(
SELECT NULL
FROM table1 t1
WHERE t1.common_id = common.common_id
)
...
Find all records which have a count of an association greater than zero
... To remove the duplicates, use
Project.joins(:vacancies).group('projects.id')
UPDATE:
As pointed out by @Tolsee, you can also use distinct.
Project.joins(:vacancies).distinct
As an example
[10] pry(main)> Comment.distinct.pluck :article_id
=> [43, 34, 45, 55, 17, 19, 1, 3, 4, 18, 44, ...
How to select a single field for all documents in a MongoDB collection?
...ery. In the result set, only the item and qty fields and, by default, the _id field return in the matching documents.
db.inventory.find( { type: 'food' }, { item: 1, qty: 1 } )
In this example from the folks at Mongo, the returned documents will contain only the fields of item, qty, and _id.
Thus,...