In my app, I set my users information like:
set users:alex:age 30
set users:alex:heigth 1.8
set users:sly:age 32
set users:sly:heigth 1.95
Is there a way to get the list of users (alex, sly) without using a Set Or do I need to use a Set like:
sadd users users:alex
sadd users users:sly
and get the users with
smembers users
?
Using a set is the proper way to do it. You can also use keys users:*:age to get all users, but that would be much slower.
Also, instead of using users::age, users::height, you should use a hash in users: with "age" and "height" as keys.
Related
This might be a very stupid question but for the life of me I can't get it to work. I want to create a field in my table called "One" and it's value for all records in the table needs to be 1.
E.G.
Field1 One
A 1
B 1
C 1
.
.
.
I set the field to a number and tried the auto enter data and typed 1 in the data field but it's not updating the values.
Any help is greatly appreciated!
Thanks in advance
Simply put, Auto Enter applies to when the record is first created. One can do various other options, but this is the basic use of Auto Enter on a field. You set the value to be auto-entered in the field's options panel under Manage Database; a fixed value, calculated value and so on. This works on all versions of FileMaker.
That said, if this is to be a static value of 1 for all records, you might want to look into a calculation field with a result of 1 and possibly using global storage. This will not work if you need the user to be able to change the value.
I have to import about 2000 products in Magento and since the native import tool is very slow we decided to use magmi.
What we have done is create about 20 custom attributes, created a new attribute set (based on the default set) and add all these attributes to the new custom set.
(Magento is set up as multistore for a .de/.at domain)
With magmi I made a test import with one single test article, the import runs fine (no errors). But in the backend there are a few fields missing (like "price"); Not the values are missing but the fields are simply not shown.
Here is an example of the csv I use:
"attribute_set";"type";"sku";"websites";"name";"description";"short_description";"z_bottled";"status";"tax_class_id";"category_ids";"price";"special_price"
"z_article";"Simple Product";"123456";"base";"MAGMI Produkt";"Description";"Kurzbeschreibung";"2012";"1";"2";"87,88,105";"123";"123"
you lack "store" column, put "admin" in it or use value replacer plugin to force it to "admin" value.
however,this may also work without since magmi is "normally" able to default it to this value.
also ,maybe you need to launch flat reindexing & price reindexing.
I am trying to create a login for my database and I don't want to use the Microsoft way of doing so. I want to have the users login with a username and password then have that information verified in the "tblUsers" table.
UserID LoginID Level LevelID
jpurk jack23 admin 3
krimes kitty editor 2
lwalms low34 reader 1
I got as far as verifying the "UserID" and "LoginID" using dlookup
Nz(DLookup("[LoginID]", "tblUsers", "[UserID] = '" & Me.txtUserID & "'"), "")
=Me.txtPassword
The problem I have now is that I want certain items on the menu unavailable to users without the proper Level; If they are only an "editor" or a "reader", then I don't want them to have access to the "administrative" button where I have placed all admin forms.
After I use dLookup to verify the username and password, how do I now find out their "Level" and assign rights to different menu items? Thank you.
Assuming your DLookup has found an existing LoginID value, you can use another to retrieve that user's LevelID. Then enable/disable the administrative command button based on their LevelID.
I'll suggest something like this in Form Load:
Dim lngLevelID As Long
lngLevelID = DLookup("[LevelID]", "tblUsers", "[LoginID] = " & Me.txtLoginID)
Me.cmdAdmin.Enabled = (lngLevelID = 3)
Notes: That assumes you've previously loaded the user's LoginID number into a text box named txtLoginID. txtLoginID could be hidden if you don't want the users to see it. Or you can grab the LoginID value by some other method.
If you have one-to-one matches between Level and LevelID, you shouldn't need to store both values in tblUsers. You can create a UserLevels lookup table to hold both, and store just the LevelID in tblUsers as a foreign key to the appropriate row in UserLevels.
Finally, the strategy you're using can work, but the security is shaky. As "guidance" to users willing to follow the rules, it's OK. But it can be easily circumvented by even unsophisticated users. Look for a different approach if your security needs are stringent.
I have a REST service that allows people to put in a course title as part of the query to get scores, but, sometimes they may want to get a group, such as Calculus% for Calc 1, 2 and 3.
But, what is the best way to give them an option that makes sense?
For example, I have http://localhost/myrest/any/any/Calculus III
where the first two parameters are student id and some grade category.
I don't think having http://localhost/myrest/any/any/contains/Calculus III is a good use as then I will need to force them to use equals if that is what they are looking for.
Another option is http://localhost/myrest/any/any/Calculus% or http://localhost/myrest/any/any/%Calc% is another option, but then you have removed the option to easily use % as an allowed character.
So, to give additional filtering options in a REST URL, what is the best (defined as simplest/most intuitive for the user) way to allow contains or starts with.
In your system, would the following query list all subjects in the grade category?
http://localhost/myrest/any/any/
If yes, then one option you can consider is extracting the non-exact subject name into a GET parameter. Thus without breaking the current logic where having a full name of the subject in the URL provides the score for that subject, you'd also have the ability to filter the list of subjects within the same grade category by means of the GET parameter.
For example:
http://localhost/myrest/any/any/?search=Calculus*
... could provide a result like this:
<subjects>
<subject uri="/myrest/any/any/Calculus%20I">A</subject>
<subject uri="/myrest/any/any/Calculus%20II">B</subject>
<subject uri="/myrest/any/any/Calculus%20III">C</subject>
</subjects>
I have User model object with quite few fields (properties, if you wish) in it. Say "firstname", "lastname", "city" and "year-of-birth". Each user also gets "unique id".
I want to be able to search by them. How do I do that properly? How to do that at all?
My understanding (will work for pretty much any key-value storage -- first goes key, then value)
u:123456789 = serialized_json_object
("u" as a simple prefix for user's keys, 123456789 is "unique id").
Now, thinking that I want to be able to search by firstname and lastname, I can save in:
f:Steve = u:384734807,u:2398248764,u:23276263
f:Alex = u:12324355,u:121324334
so key is "f" - which is prefix for firstnames, and "Steve" is actual firstname.
For "u:Steve" we save as value all user id's who are "Steve's".
That makes every search very-very easy. Querying by few fields (properties) -- say by firstname (i.e. "Steve") and lastname (i.e. "l:Anything") is still easy - first get list of user ids from "f:Steve", then list from "l:Anything", find crossing user ids, an here you go.
Problems (and there are quite a few):
Saving, updating, deleting user is a pain. It has to be atomic and consistent operation. Also, if we have size of value limited to some value - then we are in (potential) trouble. And really not of an answer here. Only zipping the list of user ids? Not too cool, though.
What id we want to add new field to search by. Eventually. Say by "city". We certainly can do the same way "c:Los Angeles" = ..., "c:Chicago" = ..., but if we didn't foresee all those "search choices" from the very beginning, then we will have to be able to create some night job or something to go by all existing User records and update those "c:CITY" for them... Quite a big job!
Problems with locking. User "u:123" updates his name "Alex", and user "u:456" updates his name "Alex". They both have to update "f:Alex" with their id's. That means either we get into overwriting problem, or one update will wait for another (and imaging if there are many of them?!).
What's the best way of doing that? Keeping in mind that I want to search by many fields?
P.S. Please, the question is about HBase/Cassandra/NoSQL/Key-Value storages. Please please - no advices to use MySQL and "read about" SELECTs; and worry about scaling problems "later". There is a reason why I asked MY question exactly the way I did. :-)
Being able to query properties directly is one of the features you lose when moving away from SQL, so you need a way to maintain your own index to let you find records.
If your datastore does not have built in indexing or atomic list operations, you will need to deal with the locking issues you mention. However, indexing doesn't necessarily need to be synchronous - maintain a queue of updated records to be reindexed and you have a solution for 3 that can be reused to solve 2 also.
If the index list for a particular value becomes too large for the system to handle in a single list, you can replace the list of users with a list of lists. However, if you have that many records with the same value it probably isn't a particularly useful search criteria anyway.
Another option that is useful in some cases is to use a seperate system for the indexing - for example you could set up lucene to index the records in your main datastore.
I guess i would have implemented this as a MapReduce job, which would run on schedule.
Each search word, would be a row-key with lookup to UID.
Rowkey:uid1
profile:firstName: Joe
profile:lastName: Doe
profile:nick: DoeMaster
Rowkey: uid2
profile:firstName: Jane
profile:lastName: Doe
profile:nick: SuperBabe
MapReduse indexes all searchable properties and add them with search word as row key
Rowkey: Jane
lookup:uid: uid2
Rowkey: Doe
lookup:uid: uid2, uid1
Rowkey: DoeMaster
lookup:uid: uid1
..etc
Now, if you need to update the index list on the fly as a user change, you would write the change directly to the index base, by remove uid value from index and add to another row key. In case of this happens at the same time, temporary locking could be implemented.
For users being removed, an additional attribute telling the state of the user could be use to filter them out from search.
Adding additional search word isn't very hard, since its just about which name:value you want to index. you could filter search more also by adding type attribute to your row key/keyword. i.e boston - lookup:type: city.
The idea is to maintain your own row key based search index inside hbase.