Fix crash during migration on Android by avoiding to throw exceptions....

Fix crash during migration on Android by avoiding to throw exceptions. Apparently exceptions do not work reliabily on android, at least not with our current toolchain and compilation options.

src/db/main-db.cpp

@@ -1256,13 +1256,11 @@ template<typename T>
 static T getValueFromRow (const soci::row &row, int index, bool &isNull) {
 	isNull = false;
 
-	try {
-		return row.get<T>(size_t(index));
-	} catch (const exception &) {
+	if (row.get_indicator(size_t(index)) == soci::i_null){
 		isNull = true;
+		return T();
 	}
-
-	return T();
+	return row.get<T>(size_t(index));
 }
 
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