TIMESTAMP

In the Ultra Transcenders books

DBX-DEPDBX-GENAI

Each book explains TIMESTAMP in context, with comparison tables and the common traps.

Terms in this definition

• VARIANT

  A type for semi-structured data like JSON whose structure isn't fixed, available from Databricks Runtime 15.4. It is preferred to storing JSON as strings but can't serve as a partition column.

Related terms

• Aging and scavenging

  Removes stale dynamically registered DNS records once both the no-refresh and refresh intervals (seven days each by default) have passed after their timestamp.

• Auto-TTL

  Rows older than a set number of days, measured from a timestamp column, are removed automatically (DELETE ROWS ... DAYS AFTER). It covers Unity Catalog managed Delta or Iceberg tables plus pipeline streaming tables, depends on predictive optimization, and runs at no guaranteed time.

• bin()

  A KQL function that groups values by rounding numbers, timespans or datetimes down to the nearest multiple of a chosen size; paired with summarize, bin(Timestamp, 1h) gives hourly buckets. floor() behaves the same way, and bin_at() lets you pick where the buckets start.

• Delta generated columns

  Columns in a Delta table that are filled in automatically from other values in the same row each time data is written, and then saved. A typical use is deriving a DATE from a timestamp to help skip files; identity columns are one particular kind.

• Detect data changes

  An extra incremental refresh option: nominate a timestamp column, for instance one recording when rows were last modified, and Power BI skips any partition whose latest timestamp hasn't moved since the last run.

• dynamic_version

  Applies only to whl artifacts in a bundle: it changes the wheel's version using the file's timestamp, so a serverless job picks up new code with no manual version edit.

• Full-text population

  Filling or refreshing a full-text index, done as a full population, through change tracking (manual or automatic), or incrementally, which needs a timestamp column.

• Late Input Events

  Metric in Stream Analytics that counts events which arrived after the late arrival tolerance window, so were either dropped or given an adjusted timestamp.