I'm trying to implement a search query in Prisma for a float. Right now I'm using equals, but that means you have to type the exact number. I'd like to implement something like a partial string search - i.e. if I type in '36' it would bring back '360' or '23.36'
The only options I see are greater than or less than or equals - how do you handle number searches? I would be OK even if it only had 'starts with' logic, so I could get back 36 or 362 or 3612, but I can't figure out any way to accomplish this.
Is there any way to achieve this with Prisma?
The only way to accomplish something like this that I could see is to use String as the type within Prisma schema and within your code consume the values by parsing them into floats again / stringifying them.
This way you could use string operators within Prisma, so for example { floatAsString: { contains: '36' } } would find 360 and 23.36
If you keep it as floats in the Prisma schema there are no operators to achieve this in the Prisma API.
Related
Using EFCore 6 ...
I have a variety of values in a column I want to use as the discriminator column.
There are certain values (SERVER_STS) I am mapping to entity classes
modelBuilder.Entity<QueueEntry>()
.HasDiscriminator<string>("TaskType")
.HasValue<StatusEntry>(Constants.TaskServerStatus)
.IsComplete(false);
I, ideally would want to map all the other values to generate a single entity class, QueueEntry. So something like
modelBuilder.Entity<QueueEntry>()
.HasDiscriminator<string>("TaskType")
.HasValue<StatusEntry>(Constants.TaskServerStatus)
.HasOtherValue<QueueEntry>();
I thought the IsComplete might help, but I'm only getting back the StatusEntry rows.
I can't see a way of doing this. I see there is an Expression overload for the HasDiscriminator method, but can't quite get my head around whether this might give me what I need.
So is this possible or will I need to segregate the entities at a higher level?
I have a sql query suppose
sqlQuery="select * from %s_table where event like '%holi%'"
listCity=["Bangalore","Mumbai"]
for (city<- listCity){
print(s.format(city))
}
Expected output:
select * from Bangalore_table where event like '%holi%'
select * from Mumbai_table where event like '%holi%'
Actual output:
unknown format conversion exception: Conversion='%h'
Can anyone let me how to solve this, instead of holi it could be anything iam looking for a generic solution in scala.
If you want the character % in a formatting string you need to escape it by repeating it:
sqlQuery = "select * from %s_table where event like '%%holi%%'"
More generally I would not recommend using raw SQL. Instead, use a library to access the database. I use Slick but there are a number to choose from.
Also, having different tables named for different cities is really poor database design and will cause endless problems. Create a single table with an indexed city column and use WHERE to select one or more cities for inclusion in the query.
I have some data in a postgres table with one column called version (of type varchar). I would like to use my own comparison function to to order/sort on that column, but I am not sure what is the most appropriate answer:
I have an JS implementation of the style comp(left, right) -> -1/0/1, but I don't know how I can use it in a sql order by clause (through plv8)
I could write a C extension, but I am not particularly excited about this (mostly for maintenance reason, as writing the comparison in C would not be too difficult in itself)
others ?
The type of comparisons I am interested are similar to version string ordering used in package managers.
You want:
ORDER BY mycolumn USING operator
See the docs for SELECT. It looks like you may need to define an operator for the function, and a b-tree operator class containing the operator to use it; you can't just write USING myfunc().
(No time to test this and write a demo right now).
To achieve best performance and validation convenience, which of these annotations are needed for a String field?
database: MySQL
A field to store district name
#Column(length=50) // javax.persistence.Column
Is this going to be converted to varchar(50)? Or I need this one specifically:
#Column(columnDefinition='varchar(50)')
And another two annotations
#MaxLength(50) // play.data.validation.Constraints.MaxLength
#Length(max=50) // com.avaje.ebean.validation.Length, is this one useful or not required anyway?
public String districtName;
I think I need #Column(length=50) for definition and #MaxLength(50) for validation at same time? Or one of these two will imply the other one automatically?
Thanks.
As far as I know, when we mark String variable with these annotation:
#javax.persistence.Column(length=50)
#javax.persistence.Column(columnDefinition='varchar(50)'). Note: I am use postgreSQL, and this will create column definition with character varying data type
#com.avaje.ebean.validation.Length(50)
the three annotations above has the same purpose. Those will create column definition with character varying data type and length of 50 characters on database.
Without the #Constraint.MaxLength(50), you will get exception like below when you entered input value whose length greater than 50:
Execution Exception
[ValidationException: validation failed for: models.TheModel]
I think, there should be a way to handle above exception, but honestly I don't know how to do that until now.
Advice
My advice for you is to choose one out of the 3 annotations above (It is your preference) with the use of anotation #Constraint.MaxLength(50). For me, it is the easiest and the simplest way, and you can easily make the form using play framework scala-template-helper.
I am using Rogue/Lift Mongo record to query MongoDb. I am trying to create different query according to the sort field name. I have therefore a string name of the field that I want to use to sort the results.
I have tried to use Record.fieldByName in OrderAsc:
...query.orderAsc (elem => elem.fieldByName(columnName).open_!)
but I obtain "no type parameter for orderAsc".
How can I make it working? Honestly all the type programming in Rogue is quite difficult to follow.
Thanks
The problem is that you cannot dynamically generate a query with Rogue easily. As solution I used Lift Mongo Db that allows the usage of strings (without compile checking) for these kind of operations that requires dynamic sorting.