我使用了ScalaQuery和Scala.
如果我有一个Array [Byte]对象,我该如何将它插入表中?
object TestTable extends BasicTable[Test]("test") {
def id = column[Long]("mid", O.NotNull)
def extInfo = column[Blob]("mbody", O.Nullable)
def * = id ~ extInfo <> (Test, Test.unapply _)
}
case class Test(id: Long, extInfo: Blob)
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我可以使用def extInfo = column[Array[Byte]]("mbody", O.Nullable)BLOB类型字段定义使用的方法,如何操作(UPDATE,INSERT,SELECT)?
BTW:没有ScalaQuery标签
val xsa = List(1,2,3)
val xsb = List(1,2,3)
for (i <- 0 until xsa.size) {
val a = xsa(i)
val b = xsb(i)
println(a + "_" + b)
}
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我想简化长度等于'List或Array.我希望这样做:
for (a <- xsa; b <- xsb)
println(a + "_" + b)
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但为什么它只迭代xsb一次?
var set = TreeSet(5,4,3,2,1)
println(set)
val diffSet: TreeSet[Int] = set
// if I change above code to val diffSet: Set[Int] = set
// the result is unsorted set.
for (i <- diffSet; x = i) {
println(i)
}
println("-" * 20)
// the above code translates to below and print the same result
val temp = diffSet.map(i => (i, i))
for ((i, x) <- temp) {
println(i)
}
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我的问题是,如果我定义了这样的方法:
def genSet:Set[Int] = {
TreeSet(5, 4, 3, 2, 1)
}
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当我想使用for循环时 …