Bydefault moqui generates 100000 and so on as IDs for entities. i.e 100000,100001,100003... But i want AMG000100000 as start point so that it will contnue as AMG000100001,AMG000100002 and so on. I tried it various ways but nothing is working. Can any one suggest.
You can set a prefix for primary (single key) sequenced IDs per-entity with the entity.#sequence-primary-prefix attribute and for all entities using the entity-facade.#sequenced-id-prefix attribute. This will not left zero pad the numeric part of the sequence as you show in your examples, there is currently no OOTB support for something like that (you would have to change the framework code, or in your code that creates records augment the value coming back from the framework, or just your own sequencing code).
you can use the sequence-primary-prefix field on the entity definition to set a prefix, however without the zero padding as David indicated.
Related
I have a table with guid identifier and one field that is a 5 characters string that can be specified by user, but it is optional, and it should be unique per user. I'm looking for a way to have this field always there, even if user doesn't specify it. The easiest approach is to have it like "00001", "00002"... etc. in case that user doesn't specify it, it is stored like this. I'm using SQL and entity framework core. What is the best way to achieve this?
EDIT: maybe trigger that will check after insert if that field is not specified and then just take current row number and convert it to string? does this make sense?
Cheers
Setting a default value to '00001' can be done define the field with:
NOT NULL DEFAULT right('0000' || to_char(SomeSequence.nextval),5) (pseudo-code to be adapted to the DBMS you are connected to).
Compared to the solution in your EDIT, this will at least guarantee that 2 inserts at the same time from 2 different users get assigned different values.
The real problem comes with the unique constraint on the column. This does not work nicely when mixing manual input with calculated values.
If as a user, I input (manually) 00005, then the insertion will fail when SomeSequence reaches 5.
I think this problem will exist regardless of how you implement the generation of values (sequence, trigger, external code, ...)
Even if you are fine with coding some additional (and probably complicated) logic to manage that, it will probably decrease concurrency.
How to create an Endeca query on combination of multiple fields [just like where clause in sql query]. Suppose we have three fields indexed are -
empId
empName
empGender
Now, I need a query like "where empName like 's%' AND empGender=male"
Thanks.
Firstly,
Checkout Record Filters in the Advanced Development Guide.
If you are trying to use a Record Filter on a property, you will need to enable it explicitly in Developer Studio for that property, while your Dimensions will automatically have the ability to apply a Record Filter. This will help when you have explicit values to filter on, for example empGender.
Your Record Filter can then look as follow:
Nr=AND(empGender:male)
You can further use the Ntk parameter to specify fields to search on so assuming your empName field is enabled for wildcard searching (configure this in Developer Studio) searching this field will look as follow:
Ntk=empName&Ntt=s*
So assuming your properties have been configured correctly, your example above will probably end up looking as follow:
Nr=AND(empGender:male)&Ntk=empName&Ntt=s*
To take this one step further, you can specify Search Filters (ie. Ntk + Ntt parameters) together. I haven't tried this for wildcards so you'll need to confirm that yourself but to combine Search Filters you delimit them with |
Ntk=empName|empId&Ntt=s*|1234*
I suggest you manually build up queries in the Reference Application to confirm you get your expected results and then start to code this up in your application.
radimbe, the problem with record filters for this use case is that they need to be precise. This means you don't get pelling correction, thesaurus expansion, case insensitivity or stemming. It's very unlikely that a user will input precise information like this.
Saraubh, you can do a boolean search to do OR text search queries. You can also use the Endeca Query Language to specify a complex set of boolean logic that goes beyond boolean search and which would incorporate spelling correction, stemming, etc.
In general though, I think for an application like this, you should move away from searching specific individual fields simultaneously and make use of the faceting capabilities of dimensions to guide the user. Additionally, a search box that searches many fields in combination simultaneously in order of importance is really the way to go for a simplified user interface for this sort of application.
If I have a POCO class with ResultColumn attribute set and then when I do a Single<Entity>() call, my result column isn't mapped. I've set my column to be a result column because its value should always be generated by SQL column's default constraint. I don't want this column to be injected or updated from business layer. What I'm trying to say is that my column's type is a simple SQL data type and not a related entity type (as I've seen ResultColumn being used mostly on those).
Looking at code I can see this line in PetaPoco:
// Build column list for automatic select
QueryColumns = ( from c in Columns
where !c.Value.ResultColumn
select c.Key
).ToArray();
Why are result columns excluded from automatic select statement because as I understand it their nature is to be read only. So used in selects only. I can see this scenario when a column is actually a related entity type (complex). Ok. but then we should have a separate attribute like ComputedColumnAttribute that would always be returned in selects but never used in inserts or updates...
Why did PetaPoco team decide to omit result columns from selects then?
How am I supposed to read result columns then?
I can't answer why the creator did not add them to auto-selects, though I would assume it's because your particular use-case is not the main one that they were considering. If you look at the examples and explanation for that feature on their site, it's more geared towards extra columns you bring back in a join or calculation (like maybe a description from a lookup table for a code value). In these situations, you could not have them automatically added to the select because they are not part of the underlying table.
So if you want to use that attribute, and get a value for the property, you'll have to use your own manual select statement rather than relying on the auto-select.
Of course, the beauty of using PetaPoco is that you can easily modify it to suit your needs, by either creating a new attribute, like you suggest above, or modifying the code you showed to not exclude those fields from the select (assuming you are not using ResultColumn in other join-type situations).
AJAX autocomplete is fairly simple to implement. However, I wonder how to handle smart tag suggestion like this on SO.
To clarify the difference between autocomplete and suggestion:
autocomplete: foo [foobar, foobaz]
suggestion: foo [barfoo, foobar, foobaz], or even better, with 'did you mean' feature: [barfoo, foobar, foobaz, fobar, fobaz]
I suppose I need some full text search in tags (all letters indexed, not just words). There would be no problem to do it witch regex or other patterns for limited number of tags (even client side).
But how to implement this feature for big number of tags?
Is there any particular reason (besides URL) the tags on SO are dash separated? What about Unicode characters in tags?
I store the tags in the table with the following columns: id, tagname.
My SQL query returns objects with following fields: id, tagname, count
(I use Doctrine ORM and pgsql as default db driver.)
I would go with SELECTING them from database by REGEXP at every keypress. I did this on my sites and the was no prefrormance problem (I do not have heavy loaded server thought). If you do not like this idea, I would cash all 1-5 letters combinations which will users enter and refresh them on daily basis in separate table. If this table is indexed than you have very fast implementation.
To elaborate more on the second appreach:
Briefly: 1. Make a table SEARCHTABLE representing 1-n relationship betwean keywords (limit it to 3-4 letters) and primary IDs of tags. 2. INDEX on both fields. 3. Everytime the user makes a search do look at the SEARCHTABLE and if the combination is there, use that - very fast, as everything is indexed. If not do the regexp search and put all results to SEARCHTABLE.
Notes:
You should invalidate the table if
you add tags, but this should much
less often than a search. When
invalidating table you do not
necesarilly TRUNCATE it, you can
easily rebuild it taking all
keywords into account.
If you want to speed it up, you can "pregenerate" all two or even three
letters searches.
If you care enough, you should be using information from n-1 letter kewords to generate
the n letter keyword. It speeds the things tremendously. Imagine that user has typed "mo"
and you have shown them appropriate result from SEARCHTABLE. Than when she types "n"
giving it "mon" you need only serach trough already selected items to generate new
response.
Hope it is more comprehensive now.
I am fairly new to nHibernate and DDD, so please bear with me.
I have a requirement to create a new report from my SQL table. The report is read-only and will be bound to a GridView control in an ASP.NET application.
The report contains the following fields Style, Color, Size, LAQty, MTLQty, Status.
I have the entities for Style, Color and Size, which I use in other asp.net pages. I use them via repositories. I am not sure If should use the same entities for my report or not. If I use them, where I am supposed to map the Qty and Status fields?
If I should not use the same entities, should I create a new class for the report?
As said I am new to this and just trying to learn and code properly.
Thank you
For reports its usually easier to use plain values or special DTO's. Of course you can query for the entity that references all the information, but to put it into the list (eg. using databinding) it's handier to have a single class that contains all the values plain.
To get more specific solutions as the few bellow you need to tell us a little about your domain model. How does the class model look like?
generally, you have at least three options to get "plain" values form the database using NHibernate.
Write HQL that returns an array of values
For instance:
select e1.Style, e1.Color, e1.Size, e2.LAQty, e2.MTLQty
from entity1 inner join entity2
where (some condition)
the result will be a list of object[]. Every item in the list is a row, every item in the object[] is a column. This is quite like sql, but on a higher level (you describe the query on entity level) and is database independent.
Or you create a DTO (data transfer object) only to hold one row of the result:
select new ReportDto(e1.Style, e1.Color, e1.Size, e2.LAQty, e2.MTLQty)
from entity1 inner join entity2
where (some condition)
ReportDto need to implement a constructor that has all this arguments. The result is a list of ReportDto.
Or you use CriteriaAPI (recommended)
session.CreateCriteria(typeof(Entity1), "e1")
.CreateCriteria(typeof(Entity2), "e2")
.Add( /* some condition */ )
.Add(Projections.Property("e1.Style", "Style"))
.Add(Projections.Property("e1.Color", "Color"))
.Add(Projections.Property("e1.Size", "Size"))
.Add(Projections.Property("e2.LAQty", "LAQty"))
.Add(Projections.Property("e2.MTLQty", "MTLQty"))
.SetResultTransformer(AliasToBean(typeof(ReportDto)))
.List<ReportDto>();
The ReportDto needs to have a proeprty with the name of each alias "Style", "Color" etc. The output is a list of ReportDto.
I'm not schooled in DDD exactly, but I've always modeled my nouns as types and I'm surprised the report itself is an entity. DDD or not, I wouldn't do that, rather I'd have my reports reflect the results of a query, in which quantity is presumably count(*) or sum(lineItem.quantity) and status is also calculated (perhaps, in the page).
You haven't described your domain, but there is a clue on those column headings that you may be doing a pivot over the data to create LAQty, MTLQty which you'll find hard to do in nHibernate as its designed for OLTP and does not even do UNION last I checked. That said, there is nothing wrong with abusing HQL (Hibernate Query Language) for doing lightweight reporting, as long as you understand you are abusing it.
I see Stefan has done a grand job of describing the syntax for that, so I'll stop there :-)