Sort fights by start time in descending order and refactor saveFromStream method to use useDb block.

Signed-off-by: Chaoscaot <max@maxsp.de>

CommonCore/SQL/src/de/steamwar/sql/NodeDownload.kt

@@ -25,6 +25,7 @@ import org.jetbrains.exposed.v1.core.dao.id.IdTable
 import org.jetbrains.exposed.v1.core.eq
 import org.jetbrains.exposed.v1.dao.IntEntity
 import org.jetbrains.exposed.v1.dao.IntEntityClass
+import org.jetbrains.exposed.v1.javatime.CurrentTimestamp
 import org.jetbrains.exposed.v1.javatime.timestamp
 import java.security.MessageDigest
 import java.sql.Timestamp
@@ -33,7 +34,7 @@ import java.time.Instant
 object NodeDownloadTable: IdTable<Int>("NodeDownload") {
     override val id = reference("NodeId", SchematicNodeTable).uniqueIndex()
     val link = varchar("Link", 255)
-    val timestamp = timestamp("Timestamp").default(Instant.now())
+    val timestamp = timestamp("Timestamp").defaultExpression(CurrentTimestamp)
 }
 
 class NodeDownload(id: EntityID<Int>) : IntEntity(id) {
@@ -49,7 +50,9 @@ class NodeDownload(id: EntityID<Int>) : IntEntity(id) {
             digest.update("${Instant.now()}${schem.owner}${schem.nodeId}".toByteArray())
             val hash = digest.digest().joinToString("") { "%02x".format(it) }
             useDb {
-                new {
+                findByIdAndUpdate(schem.id.value) {
+                    it.link = hash
+                } ?: new {
                     nodeId = schem.id.value
                     link = hash
                 }