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Retrieving the last record in each group - MySQL
..._messages AS (
SELECT m.*, ROW_NUMBER() OVER (PARTITION BY name ORDER BY id DESC) AS rn
FROM messages AS m
)
SELECT * FROM ranked_messages WHERE rn = 1;
Below is the original answer I wrote for this question in 2009:
I write the solution this way:
SELECT m1.*
FROM messages m1 LEFT JOIN mes...
Get specific object by id from array of objects in AngularJS
...s to get only one object from the array. So I d like for example Item with id 1.
17 Answers
...
How to create relationships in MySQL
...e innodb you can create it like this:
CREATE TABLE accounts(
account_id INT NOT NULL AUTO_INCREMENT,
customer_id INT( 4 ) NOT NULL ,
account_type ENUM( 'savings', 'credit' ) NOT NULL,
balance FLOAT( 9 ) NOT NULL,
PRIMARY KEY ( account_id ),
FOREIGN KEY (customer_id) REFERE...
How can I get a channel ID from YouTube?
...m my channel using the YouTube Data API V3 .
For that I need my channel ID.
I've tried to find my channel ID from my YouTube account, and I failed in every single way.
If anyone have a single tip for me, I would be incredible glad.
...
Need to list all triggers in SQL Server database with table name and table's schema
...
SELECT
sysobjects.name AS trigger_name
,USER_NAME(sysobjects.uid) AS trigger_owner
,s.name AS table_schema
,OBJECT_NAME(parent_obj) AS table_name
,OBJECTPROPERTY( id, 'ExecIsUpdateTrigger') AS isupdate
,OBJECTPROPERTY( id, 'ExecIsDeleteTrigger') AS isdelete
,OBJ...
mongodb group values by multiple fields
...ems to $push to an array.
db.books.aggregate([
{ "$group": {
"_id": {
"addr": "$addr",
"book": "$book"
},
"bookCount": { "$sum": 1 }
}},
{ "$group": {
"_id": "$_id.addr",
"books": {
"$push": {
"...
How to select html nodes by ID with jquery when the id contains a dot?
...
@Tomalak in comments:
since ID selectors must be preceded by a hash #, there should be no ambiguity here
“#id.class” is a valid selector that requires both an id and a separate class to match; it's valid and not always totally redundant.
The corr...
What is the difference between save and insert in Mongo DB?
...s essentially the same.
save behaves differently if it is passed with an "_id" parameter.
For save, If the document contains _id, it will upsert querying the collection on the _id field, If not, it will insert.
If a document does not exist with the specified _id value, the save() method performs an...
Passing data to a bootstrap modal
I've got a couple of hyperlinks that each have an ID attached. When I click on this link, I want to open a modal ( http://twitter.github.com/bootstrap/javascript.html#modals ), and pass this ID to the modal. I searched on google, but I couldn't find anything that could help me.
...
What are valid values for the id attribute in HTML?
When creating the id attributes for HTML elements, what rules are there for the value?
23 Answers
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