I am using an

alias

to create a sub-query and then using that sub-query in a join. It looks like once you use an

alias

you can no longer reference the columns in the

ResultRow

by the original table's columns. Keys in the

ResultRow

from the alias look like

org.jetbrains.exposed.sql.Alias.name

. Is there any way to avoid this? I have common mapping code that assumes it can use the table class to reference columns. e.g (

DataSourceTable.name

).

It appears that version

17.1

has broken the mysql

MATCH(...) AGAINST(...)

function - now the generated sql looks like this:

MATCH(... AGAINST(...)

. no closing right

)

on the MATCH.

Is there an example of creating custom column types anywhere?

Hey all, is the best way to return the value of a sum to create an aliased field and pass it into the query like so? Or can I just refer to the column in the

.get()

on the query via the

.sum()

method on the column? Here’s what I have right now:

val sumAlias = TransactionsTable.amount.sum().alias("campaignTotal")
TransactionsTable.slice(sumAlias)
    .select { TransactionsTable.campaignID eq campaignID }
    .limit(1)
    .firstOrNull()
    ?.get(sumAlias)

Hi! Is there any way to simulate a select failure with DSL API during testing?

Hi @tapacin the future we will be able to create your own ColumnType?

is it possible to return the entire row you’ve just inserted with .insert? I know there’s insertAndGetId, but I want to return the entire row.

What migration tool are people using with Exposed?

Hey guys, I'm quite new to exposed and pretty sure I'm missing something:

override fun getColorByCompany(company: String): List<String> {
        val color = transaction { Companies
                .slice(Companies.color)
                .select { Companies.name eq company }
                .map { it.toString() }
        }
       return color
    }

How can I get a single string as result and not a list of strings? Or should I convert it afterwards for myself? Thanks in advance!

i am using now exposed for a few month and i have to say that this article in combination with the github repo was an eye opener 🙂 https://touk.pl/blog/2019/02/12/how-we-use-kotlin-with-exposed-at-touk/

Hi all, it should be possible to write data and then immediately read that data within the same transaction right? In our code, this works except for one special case, in which the data only shows after the transaction block completes. I don't fully understand the "Working with Coroutines" section in the wiki where it says: " If you want to use the result and execute another queries within the same transaction you can use andThen function."

val launchResult = suspendedTransactionAsync(<http://Dispatchers.IO|Dispatchers.IO>, db = db) {
    FooTable.selectAll().count()
}.andThen { count ->
    BarTable.select { BarTable.value eq count }.map { it[BarTable.name] }
}

here it seems that the result of the count is only available to the remaining code when passed via andThen function. when exactly is it necessary to use the andThen function? would this not work?

val launchResult = suspendedTransactionAsync(<http://Dispatchers.IO|Dispatchers.IO>, db = db) {
    val count = FooTable.selectAll().count()
   BarTable.select { BarTable.value eq count }.map { it[BarTable.name] }
}

Hi everyone. Does anyone have implemented a dynamic field update. I mean, one function that update the given property with given value (maybe with generics) ?

Hi folks. I just found a bug i my exposed DAO code. The following code returned incorrect value (testing against object instance) collection member : val existingVote = this.votes.firstOrNull { vote -> vote.votedBy == voter } This was fixed by testing against id's : val existingVote = this.votes.firstOrNull { vote -> vote.votedBy.id == voter.id } Why can't I trust testing against object instance ? Shouldnt this be referenced somewhere in the documentation ? Why exposed library doesn't provide a comparison overload operator to compare two IntEntity object ? (this was tested with 0.17.4) Edit again : If i make my class inherit of this class below, this fix my problem ... open class MyIntEntity(id: EntityID<Int>) : IntEntity(id) { override fun equals(other: Any?): Boolean { if (other !is IntEntity) return false return other.id == this.id } } I believe this is because separate instance object have been created by two different transactions ... anyway, it should make sense to expect that such object are somehow the same because they have the same id's ? What do you thing ? Did I found a bug ? Where should I report it ? Last edit ( 😉 ) : I made a sample project to show-case the problem : https://gitlab.com/jfburdet/tstexposed/blob/master/test/kotlin/ComparisonTest.kt ... feel free to clone it and have a look

Is there a column type that takes a

Collection

of

String

? I am having issue with inserting data into postgresql array column Or do I to parse it to an acceptable format myself? I am getting this error:

Caused by: org.postgresql.util.PSQLException: ERROR: column "images" is of type character varying[] but expression is of type character varying

Exposed 0.17.4 released with critical fix related to transaction isolation. Please update.

Hey guys. I need your help with suspended transactions. When I do:

newSuspendedTransaction(<http://Dispatchers.IO|Dispatchers.IO>, database) {
    Ticket.all().count()
}

It fails with

org.h2.jdbc.JdbcSQLNonTransientConnectionException: Database is already closed (to disable automatic closing at VM shutdown, add ";DB_CLOSE_ON_EXIT=FALSE" to the db URL) [90121-199]

Database is H2

Just want to confirm something involving the experimental coroutine support via

newSuspendedTransaction

. The documentation states that we shouldn’t share a transaction between multiple threads due to undefined behavior, so are we not allowed to call other suspending functions within a

newSuspendedTransaction()

block given when the suspended transaction resumes it may resume on another thread? For example:

newSuspendedTransaction(<http://Dispatchers.IO|Dispatchers.IO>) {
  val result1 = myTable.select { ... }.toList()
  // newSuspendedTransaction suspends here
  callSomeSuspendingFunction()
  // newSuspendedTransaction resumes, possibly in another thread??
  val result2 = myTable.select {...}.toList()
}

Or:

newSuspendedTransaction(<http://Dispatchers.IO|Dispatchers.IO>) {
  coroutineScope {
    repeat(5) { 
      // Should I be using suspendedTransactionAsync here?
      launch { someFunctionThatUpdatesRows() }
    }
  }
}

Just a small remark. I'd really love to use this library. However, the lack of documentation to almost everything makes it really impossible. Function name is not enough to understand what I should use. Really. There are classes like Database where there is literally not a single line of documentation. Also the

notForUpdate

function is a mystery 🙂 I just hope that I get what it really does. Also, I think that if a column has a name like

xx"yy

then it would be escaped incorrectly, however, I have a small problem with tracking the code responsible for this.

The fact that

newSuspendedTransaction

closes the current transaction at the end of the block is creating a real headache for me. I have suspend functions which will start a new suspended transaction on the IO dispatcher, but they cannot call other suspend functions doing the same thing. Is there a way around this that I’m not seeing? My current workaround is to make separate, private suspending functions which are exposed publicly via a

newSuspendedTransaction

block.

Inside a Ktor post { … } I have the following code:

val dao = newSuspendedTransaction { MyDAO.findByValueOrThrowException(value) }

// MyDAO companion (LongEntityClass)
 suspend fun findByValueOrThrowException(value: String): MyDAO {
        return withContext(<http://Dispatchers.IO|Dispatchers.IO>) {
                find { MyTable.value eq value }.firstOrNull() ?: throw RuntimeException("MyDAO not found")
      }
}

10 seconds after the exception is thrown, I get the following log message: com.zaxxer.hikari.pool.ProxyLeakTask - Connection leak detection triggered for org.postgresql.jdbc.PgConnection@5b4d25e7 on thread DefaultDispatcher-worker-1, stack trace follows: java.lang.Exception: Apparent connection leak detected As you can see, I am using Hikari for a thread pool (config.leakDetectionThreshold = 10000L, corresponding to the 10 seconds after the message appears) So am I not allowed to throw an exception and catch it outside the transaction context, or am I doing something else wrong? (I am using Postgres)

Hi! Is there a way to use DSL to insert and query with one-to-many child list as easy as the DAO espec (eg. all in one statment)?

Hi! Can anyone help me with eager loading of referrers entity I make this requests

SomeEntity.all()
                .with(SometEntity::users)
                .toList()

This command makes sql query to db for select SometEntity from SomeTable and SomeUserEntity from SomeUserTable But when i'm calling get of SometEntity.users it makes another query to db to select SomeUserEntity only for one SomeEntity

Hi, pretty new to exposed, a quick question -- can I put

dbConnect = Database.Companion.connect()

in my SpringBoot

PostConstruct

function of service, and keep using it forever? Will it timeout or get expired?

Exposed 0.17.7 was released. I hope it was the latest bugfix release in that branch as new 0.18.1 almost ready and tested (with new multiple modules and java8 time support). The whole list of bug fixes and features is here https://github.com/JetBrains/Exposed/blob/0.17.4/ChangeLog.md#0177

ey guys, I’m trying to define a clean arch for testing in my Ktor + Exposed + Hikari project. Do you know if there is any good approach for unit testing those methods that define a transaction?

Hello everyone! Exposed 0.18.1 is finally here! It is huge release which includes Java Time API support and (as a side effect) new modules system. In the future it will allow to support diffrent async drivers and dialect specific extentions. Please read https://github.com/JetBrains/Exposed/wiki/LibDocumentation#exposed-0181-and-higher to know about new modules. I was trying to make as less broken changes as possible but I advice to read https://github.com/JetBrains/Exposed/wiki/Migration-Guide before moving to 0.18.1. If you find what some cases is missing please DM me to update documentation. For some time I will support both 0.18.x and 0.17.x versions, but only critical fixes will be backported to 0.17.x branch. Please report any problems with 0.18.1 here or on github issue tracker.

just the fact that opt is nullable?

Hi, does anyone know about this problem’s solution? https://stackoverflow.com/questions/58993409/how-to-avoid-n1-query-problem-on-kotlin-exposed-when-getting-value-by-daos-r I met N+1 query problem and I’d like to know about correct solution. Thank you.

hi all. is there a way using the exposed DSL to cache results from a select transaction

how do you make a unique varchar column without indexing