toDateTime

Generic Description

Converts an input into a datetime where supported. It is documented separately because time construction, sequence ordering, window parameters, and as-of behavior materially change analytical meaning.

Simple example:

RETURN toDateTime()

Consumer-Level Explanation

Use it when strings or epoch-like values need typed temporal comparison. Prefer this function when the temporal assumption should be visible to the planner, especially for event streams, freshness checks, and sequence features.

More Detailed Explanation

toDateTime belongs to the temporal construction, conversion, or extraction surface. Use it to make time semantics explicit in the query text: whether a value is date-only, time-only, timestamp-like, duration-like, current-time dependent, or bucketed to a chosen calendar unit.

Advanced Example

This example names the event stream and operational context before applying toDateTime, which helps planner tooling preserve the intended sequence semantics.

MATCH (u:User)-[e:VIEWED]->(d:Document)
TIME e.ts BETWEEN datetime('2025-01-01T00:00:00Z') AND datetime('2025-02-01T00:00:00Z')
WITH u, e, d,
     unpivot(properties(d.metadata)) AS metadata_rows,
     date_trunc('day', e.ts) AS day_bucket,
     toDateTime(properties(d).created_at) AS focused_value
RETURN u.user_id, d.title, day_bucket, metadata_rows, focused_value
LIMIT 10

Real Use Cases

Real Limitations And Tradeoffs