asofJoin() requires name of timpestamp column names to match

[ghormann]

When trying to use asofJoin() on two TSDF records with different time series column names an exception is raised. I'm not sure if this is a considered a bug or a feature, but given that TSDF knows the column name of each TSDF object, it seems like it should be smart enough to execute the join.

Example

• tsdf_state has time column 'ts'
• tsdf_validate has time column 'EndTime'
• Running asofJoin() results in an error as it is using EndTime on tsdf_state

Workaround

If I make sure the time column is the same for both TSDF records it appears to work as expected. (Here column 'ts' is created as a copy of EndTime before creating tsdf_validate).

[tnixon]

Thanks for raising this to us, @ghormann - definitely a frustrating issue. I believe this should be fixed in the upcoming v0.2 version, but we'll be sure to double check. Maybe it makes sense to get a quick fix in here before that comes out.

[R7L208]

Triage — March 2026

Status: Not resolved — actually more restrictive on v0.2-integration. The v0.2 as_of_join requires both left and right TSDFs to have matching ts_schema (same timestamp column name AND same series ID columns). In v0.1, mismatched timestamp column names already caused issues; v0.2 enforces schema compatibility even more strictly.

Jobs to be done:

• Allow as_of_join to work when left and right TSDFs have different timestamp column names (e.g., left.ts_col="event_time", right.ts_col="trade_time")
• Add a column-mapping parameter or automatic rename/alignment step

Effort estimate: 🟢 Small (1-2 days)

Closure path: Implement timestamp column remapping in as_of_join. This is a usability improvement that removes an unnecessary constraint.