In the 4.0.17 and later build, the target table of an INSERT...SELECT can be
the same as the SELECT table (insert into table1...select ...from table1).
Does the process essentially happen in a natural lock? In other words,
could the table change between the data retrieved in the select and the time
the insert gets executed?
We used to use something like this:
Lock tables table1 write;
Hi List,
we need a FIFO-queue, who will block duplicates.
Our solution:
- sorted Set with timestamp as score
- push member if not exists
- pop member with lowest score
PUSH:
ZSCORE queueKey member
if( nil ) ZADD queueKey time() member
POP
openPipeline
ZRANGE queueKey 0 0
ZREMRANGEBYRANK queueKey 0 0
executePipeline
or we need ?:
openPipeline
MULTI
ZRANGE queueKey 0 0
ZREMRANGEBYRANK
While doing redis.call() in a lua script, can I assume that these calls are atomic (all or none)?
Thanks,
Shannon
--
Are Alter View DDL commands atomic? For example, if I have foo_1 and foo_2, and a view "select * from foo_1", if I issue "Alter view select * from foo_2" where there be any period of time will queries fail?
Keith
Does anyone know this?
In the 4.0.17 and later build, the target table of an INSERT...SELECT can be
the same as the SELECT table (insert into table1...select ...from table1).
Does the process essentially happen in a natural lock? In other words,
could the table change between the data retrieved in the select and the time
the insert gets executed?
We used to use something like this:
I have a thread that every second inserts a node like this (values may vary):
{type: "foo", value: 1}
I have a�separate�thread that uses cyper over rest to query WHERE n.type="foo" AND n.data>2
Sometimes�this latter query fails due to an error that "Node[19878] does not have an attribute 'type'". When I look at this node it has such an attribute. My only explanation is that somehow neo4j creates
Hi,
We've been evaluating the atomic update feature in Solr4.0. It would be
great if anyone can shed some light on the following.
#) There seems to be more than one way to pass data to UpdateJSON for
add/update. What would be the recommended way.
https://gist.github.com/3256587 OR https://gist.github.com/3256602
#) For atomic updates, we see that "copyField" fields are getting
appeneded.
For eg
Hi,
It is clear that findAndModify is atomic for finding and updating a document. But is it also atomic for finding and inserting a document? It is not clear from the manual so wondering if anyone can confirm its behavior.
Thanks!
Hello, as I understand send is not atomic, i.e. i have something like this
in my code:
val requests = new ArrayBuffer[KeyedMessage[AnyRef, AnyRef]]
for (message
He guys,
The new multiverse 0.7 also supports clojure like atoms. Unlike the clojure atom, where upfront you need to determine if something is a ref or atom, you can use the same ref in multiverse in transactions but also outside transactions. If you want to lift upon a transaction, you need to call the normal methods (so without atomic prefix) which will fail if no transaction is present and if you
In mongoDB, is it possible to combine Updates and a Queries into one atomic step? A very customized "findAndModify", if you will.
Thank you very much for your time. I am new to mongoDB and have received excellent guidance in this community.
We need to implement a locking mechanism for a full-reindexing SOLR server
pool. We could use a database, Zookeeper as our locking mechanism but thats
a lot of work. Could solr do it?
I noticed the core admin RENAME function
(http://wiki.apache.org/solr/CoreAdmin#RENAME) Is this an synchronous atomic
operation?
What I'm thinking is we create a solr core named 'lock' and any process that
wants to
To: "Mysql List (E-mail)"
Hi everyone,
In MyISAM tables, can LOAD DATA INFILE be considered an atomic operation under normal circumstances? What will happen if the server crashes or someone kills the thread?
Thanks,
Sergei
I have a delete statement and an insert statment. I'm replacing a line but I want
to make sure, that its deleted. The insertion is successful as per sql batch output.
But when I dump the data from the table, there is no record for the date ! Seems like
delete operation happened after the insert.
SQL Input Script
=============================== create table if not exists MSFT (date DATE
Hi all,
Now that technologies such as Reiser4 are emerging that offer atomic
filesystem operations, is it expected that MySQL
will take advantage of them?
I guess I'm asking a massive number of questions with the above
simplistic statement. Admittedly, this is currently a
Linux-centric thing (to my knowledge - corrections invited and welcome!)
and the benefit of moving some of this
Hi,
Usually when people wants a zpop like command, they do :
1- lua scripting
val = redis.call('zrange', KEYS[1], 0, 0)
if val then redis.call('zremrangebyrank', KEYS[1], 0, 0) end
return val
2- �multi/zrange/zremrangebyrank/exec with clients that supports it
Watch/multi/exec is out of the question for sorted sets with high�concurrency on them.
1 is common in google search but it's definitely
Mighty Hbase users,
I have few questions and I'd really appreciate it if someone can clarify
them.
1) I want to know if Hbase inherently supports atomic append functionality
like get and put. For my work, I would be using OpenTSDB which is a layer on
top of AsynchHBase and AsynchHBase doesnt work with HBase client (which
supports atomic append).
2) If I understand correctly, atomic append
Which is order of execution of atomic operations in the following update method?
db.foo.update({'_id': 'a'}, {'$push': {'things': 'thing1'}, '$inc': {'version': 1}
The First is '$push' and the second if '$inc' ?
Or the order of execution is unknown?
I'm trying to use an array field in Mongo as an ordered set. That is,
I want to be able to tell Mongo to append a value to the end of the
array if the array doesn't contain that value, or to move it to the
end of the array if it does, The $pushToSet operation (proposed in
this JIRA ticket: https://jira.mongodb.org/browse/SERVER-2362) would
solve my problem perfectly, but until it's done I need
I am writing an app in python.
The python couchdb lib defines a function db.update(documents), with
the comment "Perform a bulk update or insertion of the given documents
using a single HTTP request."
I know a single document update fails if my revision is old.
My question is, does a batch update fail for all documents if it fails for one?
-Dusty
