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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...
How to pass macro definition from “make” command line arguments (-D) to C source code?
...
Call make command this way:
make CFLAGS=-Dvar=42
And be sure to use $(CFLAGS) in your compile command in the Makefile. As @jørgensen mentioned , putting the variable assignment after the make command will override the CFL...
Fastest way to convert Image to Byte array
...use an object that has implemented IDisposable, then you should be sure to call Dispose() when you're done with it so that it'll clean up any resources that it has tied up. The using(){} statement just calls it for you when the object goes out of scope of that statement. So you can do myObject.Dispo...
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...
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...
nodejs get file name from absolute path?
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So Nodejs comes with the default global variable called '__fileName' that holds the current file being executed
My advice is to pass the __fileName to a service from any file , so that the retrieval of the fileName is made dynamic
Below, I make use of the fileName string ...
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...
Determine command line working directory when running node bin script
...../lib');
require(lib + '/test');
It's always relative to file where it called from and don't depend on current work dir.
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