Skip to main content

DATA_Vessel

DATA_Vessel: TvxClientDataSet

Example​

procedure ScriptEvent(var Value: variant);
begin
  CreateData(DATA_Vessel, ['Code,string,50', 'Description,string,100', 'IMONo,string,20', 'CallSign,string,20']);
  DATA_Vessel.Append;
  DATA_Vessel['Code'].AsString := 'VESSEL-001';
  DATA_Vessel['Description'].AsString := 'Example vessel';
  DATA_Vessel['IMONo'].AsString := '0000000';
  DATA_Vessel['CallSign'].AsString := 'EXAMPLE';
  DATA_Vessel.Post;
  Value := DATA_Vessel.RecordCount;
end;

Usage​

DATA_Vessel provides the friendly dataset conventionally used for VxData vessel-master working data.

Conventional VxData context

The current Vessel table is application scoped and stores code/description, MMSI, IMO number, call sign, vessel type, nation, dimensions/capacity, validity, synchronisation and audit data.

This convention guides queries and field names; it is not a runtime schema contract. Custom SQL, configuration and customer extensions may return a different subset, aliases or additional columns. Use FindField for optional fields and validate types at the integration boundary.

Behaviour, lifecycle and side effects

  • Velox loads all returned rows into memory and preserves fetched string whitespace. Large results can use substantial memory.
  • Navigation, filtering, indexing and edits mutate the shared object. Closing or recreating it invalidates retained fields, bookmarks and record positions.
  • Post updates the client dataset; it does not prove an external database write or transaction commit. Persistence belongs to the function or SQL used for that purpose.
  • Data helpers commonly catch and log SQL or creation failures, potentially leaving the object inactive or reset. Invalid field, conversion and dataset-state operations can still raise.
  • Action cleanup closes friendly datasets. Velox owns the object; scripts must not free it or rely on its records surviving another action execution.
  • The mutable dataset and cursor are not thread-safe. Do not pass the reference to asynchronous work or allow nested code to reposition it without an explicit contract.

Additional Technical Info​

DATA_Vessel is an action-owned friendly dataset intended for the role described below. It is a live TvxClientDataSet reference; its name does not load data, select a connection, execute SQL or impose a field layout.

Runtime binding and identity

Velox constructs the object with the action and binds DATA_Vessel to TvxActionMan.FData60. Its diagnostic dataset name is DATA_Vessel.

The dataset begins inactive and without fields. CreateData, Data query helpers and load methods can each replace its schema and records. Every script using the action observes the same live cursor, filters, indexes and edits until it is closed or repopulated.

Implementation and naming cautions

Stored identifiers and dimensions are reference data, not live AIS position, verified registry status, seaworthiness, capacity availability or safety advice. Preserve leading characters in identifiers and validate the source before operational use.

The friendly suffix does not validate record type, authenticate a user or party, enforce application/tenant scope, apply foreign keys or prevent reuse for unrelated data.

Related entries

External references

Created 2026-07-15