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• Snapshot CDC streaming table
  • Minimal example
  • Options
  • Shared table and view fields
  • Action fields
  • Related guides

Snapshot CDC streaming table

mode: snapshot_cdc requires a snapshot_cdc_config block and forces create_table: true. Fields under write_target.snapshot_cdc_config:

Minimal example

Add this entry to the actions list in your flowgroup.

- name: write_customer_snapshot
  type: write
  write_target:
    type: streaming_table
    mode: snapshot_cdc
    catalog: "${catalog}"
    schema: "${silver_schema}"
    table: customer_dim
    snapshot_cdc_config:
      source: "${catalog}.${bronze_schema}.customer_snapshot"
      keys: ["customer_id"]
      stored_as_scd_type: 2

With the direct source form shown here, the containing flowgroup must also have a load action under the current relationship validator. A snapshot write using source_function can be the only action; the worked guide shows that form.

Options

Key	Type	Default	Notes
source	string	one-of	External table/path; exactly one of source / source_function.
source_function	dict	one-of	{file, function, parameters?}; file and function required.
keys	list[string]	required	Non-empty.
stored_as_scd_type	int	1	1 or 2.
track_history_column_list	list[string]	—	Mutually exclusive with track_history_except_column_list.
track_history_except_column_list	list[string]	—	Mutually exclusive with track_history_column_list.

With source_function, each parameters entry is bound as a keyword argument via functools.partial (the function must declare them as keyword-only args after *); source_function.file is copied alongside the generated pipeline and resolved relative to project root.

Shared table and view fields

These write_target fields apply to streaming_table and materialized_view. Sinks use their own field set.

Key	Type	Default	Notes
type	string	required	streaming_table, materialized_view, or sink.
catalog	string	—	UC catalog.
schema	string	—	UC namespace schema (not DDL — use table_schema for DDL).
table	string	—	Target table/view name.
create_table	bool	true	Streaming table only; snapshot_cdc and replace force true, and replace_where rejects false.
temporary	bool	false	Emitted as temporary=. temporary: true is rejected by replace_where.
private	bool	false	Emitted as private=. Creates the table for the pipeline’s lifetime without publishing it to the metastore; the dataset is visible only inside the pipeline.
comment	string	derived	Defaults to a description derived from the target table name.
table_properties	dict	—	Delta table properties.
tags	dict	—	UC tags {key: value}; applied by a generated tagging hook (REST API), not table DDL. See Unity Catalog tagging.
tags_file	string	—	Path to a unified schema/tags file (convention schemas/<table>.yaml) whose table-level tags and per-column tags supply UC tags. May be the same file as table_schema. Mutually exclusive with an inline tags mapping. See Schema and tag files.
partition_columns	list	—	Emitted as partition_cols=. Mutually exclusive with cluster_columns and cluster_by_auto: Databricks does not allow partitioning together with liquid clustering, so lhp validate and lhp generate reject the combination, even on an action with create_table: false. An empty list counts as unset.
cluster_columns	list	—	Liquid clustering; emitted as cluster_by=. With cluster_by_auto, these become the initial clustering keys. Mutually exclusive with partition_columns.
cluster_by_auto	bool	—	Auto liquid clustering. Can be combined with cluster_columns, which become the initial clustering keys; Databricks may later change the keys based on the workload. true is mutually exclusive with partition_columns.
spark_conf	dict	—	Spark configuration.
table_schema	string	—	Inline DDL, or a .ddl/.sql/.yaml/.json file path (auto-detected). A .yaml/.json file is the unified schema/tags file; its per-column type/nullable/comment are read here. Any UC tags it carries are ignored unless the same file is also set as tags_file — otherwise lhp generate warns LHP-CFG-069.
row_filter	string	—	Row-filter clause, emitted as row_filter=.
path	string	—	Storage location, emitted as path=.
database	string	—	Deprecated (removed at 1.0.0); use catalog + schema.

Added in version 0.9.2: The private field, for SDP private datasets that persist for the pipeline’s lifetime without being published to the metastore.

Action fields

These fields sit on the action, alongside write_target.

Field	Type	Default	Requirement and behaviour
name	string	required	Action name, unique within the flowgroup.
type	string	required	Always write.
source	string / list	conditional	Input view(s). Standard streaming writes and most sinks accept a list. CDC, replace, replace_where and foreachbatch use one view. Snapshot CDC takes its source inside snapshot_cdc_config. Materialized views require one of action source, target sql or target sql_path.
write_target	mapping	required	Target settings; type selects streaming_table, materialized_view or sink.
description	string	derived	Comment/docstring for the generated flow or view.
readMode	string	stream	stream or batch for standard streaming-table append flows. Replace requires streaming; replace_where reads in batch and rejects stream. Materialized views use batch queries; sinks use streaming reads. The read must match the kind of the view it reads, or lhp validate fails with LHP-VAL-070; a batch read in a standard streaming-table flow also needs once: true.
once	bool	false	Emits once=True for standard append and CDC flows. Not emitted for snapshot CDC, replace, replace_where, materialized views or sinks.
operational_metadata	bool / list	—	Accepted on the model; writes do not add metadata columns. Select columns on load or supported transform actions instead.
depends_on	list[string]	—	Extra upstream table/view references. See Dependency analysis reference.

Related guides

• Build a dimension from periodic snapshots

• All write actions