Saturday, 15 June 2013

scala - Count rows with Slick 1.0.0 -



scala - Count rows with Slick 1.0.0 -

i'm trying create query slick 1.0.0 returns row count equivalent next sql statement:

select count(*) table;

what have far is:

val query = { row <- table } yield row println(query.length)

this prints scala.slick.ast.functionsymbol$$anon$1@6860991f. also, query.length appears of type scala.slick.lifted.column. cannot find way execute query. examples can find in documentation , anywhere else not operate on column or scalaquery , not work anymore.

what can execute this?

any of these should trick:

query(mytable).list.length

or

(for{mt <- mytable} yield mt).list.length

or

(for{mt <- mytable} yield mt.count).first

update:

printing h2 database log shows lastly query, looks optimal:

03:31:26.560 [main] debug h2database - jdbc[2] /**/preparedstatement prep10 = conn1.preparestatement("select select count(1) \"mytable\" s5", 1003, 1007);

scala slick

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