SELECT * from posts
ORDER BY LEAST(
CASE WHEN ISNULL(replyto) THEN id ELSe replyto END, id
);
How to convert this to prisma or do I have to use raw query here?
I wanted to use pagination with take.
There is an open feature request to support CASE statements with Prisma. Using a Prisma raw query would be an option in this case.
Related
I'm using prisma with sql server so I can get a list of users just fine using
const res = await prisma.user.findMany()
I'd like to know how to prepend some text to one of the columns, similar to what the raw sql as below would do:
select 'abc' + field1, field2 from users
Either use Prisma's raw query mechanism or add this data in your application logic after you fetch the data.
Currently I have a PostgreSQL query which calculates expression:
SELECT sum(timestamp2 - timestamp1 [some other math]) from <...> WHERE <...>.
Is there a way to do it with Slick? I tried to fetch raw data (login and logout) from database and process it, but this method is too expensive, so I need to process data on the database side.
This is how you do calculated columns
https://github.com/slick/slick/issues/1314
So in your case it will be
def ts(row: YourTableClass[_]) = row.timestamp2 -- row.timestamp1
Next you can do aggregation like shown in nmat's link
I'm trying to have a request with a case sensitive result with eloquent.
For example in my database I have
1ABC
2Abc
3abc
User::where('code', 'LIKE', "%$code%")->get() or User::where('code', '=', $code)->get()
but I have my 3 rows as result and I just want 2Abc
It's feature of the database not Laravel itself. In MySql you can define CHARACTER SET and COLLATION on different levels (DB, connection, table, column - see the docs).
In your case you must be using ci - case insensitive collaction, so you need to change that in your db.
http://dev.mysql.com/doc/refman/5.7/en/charset-mysql.html
I know how to use "DISTINCT" in Doctrine 2, but I really need to use "DISTINCT ON (field)" and I don't know how to do this with the QueryBuilder.
My SQL query looks like:
SELECT DISTINCT ON (currency) currency, amount FROM payments ORDER BY currency
And this query works perfect, but I can't use it with the QueryBuilder. Maybe I could write this query on some other way?
I would suggest that the SELECT DISTINCT ON (..) construct that PostgreSQL supports is outside the Object Relational Model (ORM) that is central to Doctrine. Or, perhaps put another way, because SELECT DISTINCT ON (..) is rare in SQL implementations Doctrine haven't coded for it.
Regardless of the actual logic for it not working, I would suggest you try Doctrine's "Native SQL". You need to map the results of your query to the ORM.
With NativeQuery you can execute native SELECT SQL statements and map
the results to Doctrine entities or any other result format supported
by Doctrine.
In order to make this mapping possible, you need to describe to
Doctrine what columns in the result map to which entity property. This
description is represented by a ResultSetMapping object.
With this feature you can map arbitrary SQL code to objects, such as
highly vendor-optimized SQL or stored-procedures.
SELECT DISTINCT ON (..) falls into vendor-optimized SQL I think, so using NativeQuery should allow you to access it.
Doctrine QueryBuilder has some limitations. Even if I didn't check if it's was possible with query builder, I do not hesitate to use DQL when I do not know how to write the query with query builder.
Check theses examples at
http://doctrine-orm.readthedocs.org/en/latest/reference/dql-doctrine-query-language.html#dql-select-examples
Hope this help.
INDEX BY can be used in DQL, allowing first result rows indexed by the defined string/int field to be overwritten by following ones with the same index:
SELECT
p.currency,
p.amount
FROM Namespace\To\Payments p INDEX BY p.currency
ORDER BY p.currency ASC
DQL - EBNF - INDEX BY
I'm using Zend Framework for my website and I'd like to retrieve some data from my PostgreSQL database.
I have a request like :
SELECT DISTINCT ON(e.id) e.*, f.*, g.* FROM e, f, g
WHERE e.id = f.id_e AND f.id = g.id_f
This request works well but I don't know how to convert the DISTINCT ON(e.id) with Zend.
It seems that I can get DISTINCT rows but no distinct columns.
$select->distinct()->from("e")->join("f", "e.id = f.id_e")
->join("g", "f.id = g.id_f");
Any idea on how to make a select with distinct column ?
Thanks for help
You probably can't do this with Zend Framework since distinct on is not part of the SQL standard (end of page in Postgres documentation). Although Postgres supports it, I would assume its not part of Zend Framework because you could in theory configure another database connection which does not offer support.
If you know in advance that you're developing for a specific database (Postgres in this case), you could use manually written statements instead. You'll gain more flexibility within the queries and better performance at the cost of no longer being able to switch databases.
You would then instantiate a Zend_Db_Apdapter for Postgres. There a various methods available to get results for SQL queries which are described in the frameworks documentation starting at section Reading Query Results. If you choose to go this route I'd recommend to create an own subclass of the Zend_Db_Adapter_Pgsql class. This is to be able to convert data types and throw exceptions in case of errors instead of returning ambiguous null values and hiding error causes.