add db constraints; add optional name for login (to be sent to members)

migration.sql

@@ -67,7 +67,7 @@ CREATE TABLE IF NOT EXISTS "log" (
 
 CREATE TABLE IF NOT EXISTS "location" (
 	"id" integer NOT NULL PRIMARY KEY AUTOINCREMENT,
-	"name" text NOT NULL
+	"name" text NOT NULL UNIQUE
 );
 
 CREATE TABLE IF NOT EXISTS "boat" (
@@ -85,7 +85,7 @@ CREATE TABLE IF NOT EXISTS "boat" (
 
 CREATE TABLE IF NOT EXISTS "logbook_type" (
 	"id" integer NOT NULL PRIMARY KEY AUTOINCREMENT,
-	"name" text NOT NULL -- e.g. 'Wanderfahrt', 'Regatta'
+	"name" text NOT NULL  UNIQUE -- e.g. 'Wanderfahrt', 'Regatta'
 );
 
 CREATE TABLE IF NOT EXISTS "logbook" (