What Is a Drag Write Mode in a Production Gantt?

A drag write mode is a toolbar selector on a scheduling Gantt that decides what a saved bar drag actually records: that the operation ran at its new position, that it merely started there, or that it is intended to run there in future. The gesture is the same in all three cases; only the meaning of the save changes. Because one of those meanings is a factual claim about history and another is a statement of intent, picking the mode before dragging is the difference between a board that documents the plant and a board that quietly misreports it. EDGEBIC by User Solutions exposes the mode as a Drag writes: selector next to the save controls.

How it works

Dragging a bar never writes anything by itself. It stages the change in memory and marks the operation as overridden. The write happens on save, and what gets written is determined entirely by the mode in force at that moment.

Record start and end. Both a recorded start and a recorded end land on the new dates. The statement is that this operation ran here. This is the default and the right choice for correcting history: the mill actually started at ten rather than eight, the job actually finished Wednesday rather than Tuesday. Recorded work is treated as fact everywhere downstream, so the operation becomes immutable to the scheduler and its hours count toward progress.

Record start only. A recorded start lands on the new position and the end stays open. The statement is that this operation began here and is still running. The operation reads as in progress, its remaining hours are still remaining, and the next scheduling run plans the rest of it forward from the real start rather than from the original plan.

Record a planned start. Nothing about actuals is written at all. What lands is a durable planner pin: the intended start of an operation that has not begun. Progress does not move, hours are not consumed, and no report treats the operation as having happened. What does change is the next scheduling run, which honors the pin for both date and machine much as it would honor a recorded start, and then dissolves the pin automatically once a real start is logged.

The three modes therefore sit on a spectrum from strongest claim to weakest. Start-and-end is history. Start-only is history in progress. Planned start is intention. The scheduler treats each with the weight it deserves, which is exactly why writing the wrong one is expensive: an intention recorded as history cannot be corrected by re-running the engine, because the engine will not re-place recorded work.

A concrete example

A job runs saw, mill, then paint. It is Tuesday morning.

The saw ran yesterday but started two hours later than planned, because material arrived late. That is history, so the planner leaves the mode on record-start-and-end, drags the saw bar to its real Monday position, and saves. The bar takes the applied state and the schedule now agrees with what the plant did.

The mill is running right now, and it started at ten rather than the planned eight. That is history in progress. The planner switches to record-start-only, drags the mill bar to a ten o'clock start, and saves. The bar takes the start-applied state, the end stays open, and the mill's remaining hours are still counted as remaining.

Sales then asks whether paint could wait until Thursday for a color change. That is intent, not history. The planner switches to planned start, drags the paint bar to Thursday morning, and saves. The bar takes the planned state. Nothing pretends the painting happened, no progress moves, and when the planner presses re-schedule the engine keeps the mill's real start, plans its remaining hours forward, and pins paint to Thursday.

Three drags, three saves, three completely different records, from one identical mouse gesture. Had all three been done in the default mode, the board would now claim that Thursday's painting was already complete on Tuesday morning.

How EDGEBIC uses it

The mode is a toolbar control rather than a buried setting because it is the most consequential choice on the board. EDGEBIC warns when a drag in the strongest mode is applied to a future operation, on the grounds that recording future work as done skews progress figures and reports, but it warns rather than blocks: the board follows an override-and-warn philosophy throughout. Changing the selector is covered in how to change the drag mode on the Gantt in EDGEBIC.

Whichever mode is used, the drag itself is staged rather than written. It joins the pending set and shows the override color until saved, which is described in what is a pending schedule change in scheduling, and the state the bar takes after the save reflects which mode wrote it, as laid out in what is an operation state in a production gantt.

The weakest of the three modes deserves separate attention because it is the one most sites underuse. It produces a durable planner pin rather than a record, described in what is a planned start pin in scheduling, and it is the only mode where a mis-click costs nothing. For the broader mechanics of moving work on the board see drag and drop rescheduling in EDGEBIC.

The takeaway

The drag write mode turns one gesture into three different statements, and the scheduler treats those statements very differently. Recorded work is immutable and counts toward progress; a pin is neither. The habit worth building is checking the selector before the first drag of a session rather than after a surprising number appears in a report, because clearing incorrect recorded dates is a repair job while switching the mode is a single click. For the wider vocabulary see the manufacturing glossary, and for the product itself see EDGEBIC.