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Nonemm/docs/n1mm-interop.md
ericek111 da9884ebf5 Open a log N1MM wrote
Three things stopped it.

A contest is keyed by ContestNR, not by ContestID. ContestID is only the
ContestInstance table's primary key; DXLOG.ContestNR refers to ContestNR, which
is what N1MM's SQLWhereString matches on. The two agree in a fresh log and
drift apart in one that has been used for a while, so we were reading one
contest's header with another contest's contacts. In a real log of 56284
contacts, joining on ContestID disagreed with the contact's own ContestName
52029 times; joining on ContestNR disagreed 109 times.

N1MM names a contest per mode: CQWWCW, CQWWSSB, CQWWRTTY, never plain CQWW.
Our contests now use those names, and N1mmContestNames turns one back into a
contest and a mode when a log is opened. The name carries the mode, so it beats
the ModeCategory column. Plain CQWW still opens, because older versions wrote
it that way.

The log columns were sized by counting characters, which was too narrow for the
headers: those are drawn in the theme's font, not the grid's monospace. The
grid sizes them now, with the character count as a floor so a column of short
values does not collapse.

Bandmap spots now age from when they arrived rather than from the time written
in them. A node with a wrong clock, or one replaying its backlog on connect,
emptied the bandmap as fast as it filled it.

Checked by opening a real 56284-contact N1MM log under Xvfb and reading the
contest and contacts back.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-08-27 16:27:35 +00:00

3.4 KiB

Opening a Nonemm log in N1MM

Checked on 2026-08-27 against N1MM Logger+ 1.0.11031 by writing a log here, copying it to a Windows machine and opening it there. N1MM read the contest, its categories and the contacts.

Three things had to be right, and none of them is obvious from the schema.

The Contest table needs a row for the contest

ContestInstance says which contest a log is; the Contest table says what that contest is. N1MM reads it in Contest.FromRow when it opens a log and throws InvalidOperationException: No current row if the row is missing, which reaches the operator as "A runtime error occurred".

So the definition row is written whenever a contest is opened, not only when it is created — a log made before this was understood gets its row the next time it is opened. ContestDefinitions.For builds the row from the contest's own rules: the display and Cabrillo names, the mode, the dupe type and the multiplier names.

The overlay category cannot be empty

An empty ContestInstance.OverlayCategory is answered with "Invalid Overlay Category:" and the log will not open. An entry with no overlay says N/A.

N1MM's list is not the Cabrillo specification's list. N1MM offers:

N/A, ROOKIE, BAND-LIMITED, TB-WIRES, OVER-50, HQ, NOVICE-TECH, EXPERT

so that is what the contest dialog offers.

The sent exchange omits the report

N1MM's contest dialog says "Omit RST: CQWW: 05". SentExchange for CQ WW is 14, not 599 14; for a serial number contest it is 001. The report is fixed for the whole contest and the entry window fills it in per contact.

Getting the schema in the first place

N1MM ships no template database. ham.s3db is built at run time by applying SQL migration files that N1MM writes out from string resources inside N1MMLogger.net.exe. To read them: decompile the executable, parse N1MMLogger.Net.Resources.resx, and take the untyped <data> entries named DXLogDDL_0001_initial_schema_and_data through DXLogDDL_0004_updates. The QSO table is DXLOG and the current PRAGMA user_version is 4.

src/Nonemm.Storage/Schema.sql is that schema, flattened to the state version 4 leaves behind.

One thing to avoid

Do not replace the database file under a running N1MM. It does not notice and throws on the next read.

A contact belongs to a ContestNR, not to the table key

ContestInstance has two numbers: ContestID, the table's primary key, and ContestNR. DXLOG.ContestNR refers to the second one. N1MM's ContestInstance.SQLWhereString reads:

" ContestNR = " + this.ContestNR + " "

In a fresh log the two numbers match, so keying on either works. In a log N1MM has been using for a while they drift apart. In one real log of 56284 contacts, joining DXLOG.ContestNR to ContestInstance.ContestID disagreed with the contact's own ContestName 52029 times; joining it to ContestInstance.ContestNR disagreed 109 times.

So ContestInstance.ContestNumber here is ContestNR, and ContestID is allocated separately when a contest is created.

N1MM names a contest per mode

CQ WW is CQWWCW, CQWWSSB or CQWWRTTY, never plain CQWW. The full list lives in the Contest table of any N1MM database. Nonemm writes the same names, and N1mmContestNames turns one back into a contest and a mode when a log is opened. The name carries the mode, so it beats whatever ModeCategory says.

Older N1MM versions wrote the CW running of CQ WW as plain CQWW. That name is still in the registry, so those logs open.