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Version: 1.31.0 (latest)

dlt.common.schema.typing

C_DLT_ID​

unique id of current row

C_DLT_LOAD_ID​

load id to identify records loaded in a single load package

C_DLT_LOADS_TABLE_LOAD_ID​

load id column in the table {LOADS_TABLE_NAME}. Meant to be joined with {C_DLT_LOAD_ID} of data tables

C_CHILD_PARENT_REF_LABEL​

Label of the implicit TTableReference between a child table and its parent table

C_DESCENDANT_ROOT_REF_LABEL​

Label of the implicit TTableReference between a descendant table and its root table

C_ROOT_LOAD_REF_LABEL​

Label of the implicit TTableReference between a root table and the _dlt_loads table

C_VERSION_SCHEMA_VERSION_LABEL​

Label of the implicit TTableReference between {LOAD_TABLE_NAME} and {VERSION_TABLE_NAME} for schema version.

C_VERSION_SCHEMA_NAME_LABEL​

Label of the implicit TTableReference between {LOAD_TABLE_NAME} and {VERSION_TABLE_NAME} for schema name.

TColumnProp​

All known properties of the column, including name, data type info and hints

TColumnHint​

Known hints of a column

TColumnSchemaBase Objects​

class TColumnSchemaBase(TColumnType, TColumnProcessingHints)

View source on GitHub

TypedDict that defines basic properties of a column: name, data type and nullable

TColumnSchema Objects​

class TColumnSchema(TColumnSchemaBase)

View source on GitHub

TypedDict that defines additional column hints

TTableSchemaColumns​

A mapping from column name to column schema, typically part of a table schema

TSchemaContractDict Objects​

class TSchemaContractDict(TypedDict)

View source on GitHub

TypedDict defining the schema update settings

UPSERT_MERGE_STRATEGIES​

Strategies that merge by primary key and share the upsert options.

MERGE_STRATEGY_OPTIONS​

Merge strategy options and the strategies that support them.

MERGE_DISPOSITION_HINTS​

Table hints that store the keys of the merge write disposition dict. The column names in the dict, like row_version_column_name, mark their columns with column hints instead.

DEFAULT_VALIDITY_COLUMN_NAMES​

Default values for validity column names used in scd2 merge strategy.

TMergeDispositionDict Objects​

class TMergeDispositionDict(TWriteDispositionDict)

View source on GitHub

strategy​

The destination picks its default strategy when not set.

TSourceFilterDict Objects​

class TSourceFilterDict(TypedDict)

View source on GitHub

source_filter​

SQL condition that selects the merge source from the loaded rows. dlt discards the other loaded rows.

TDestinationScopeDict Objects​

class TDestinationScopeDict(TypedDict)

View source on GitHub

destination_scope​

SQL condition that selects the destination rows that the merge can delete or retire.

TScd2StrategyDict Objects​

class TScd2StrategyDict(TWriteDispositionDict, TSourceFilterDict,
                        TDestinationScopeDict)

View source on GitHub

active_record_timestamp​

None marks active records with NULL.

boundary_timestamp​

None resets the boundary to the load package creation time.

TUpsertOptionsDict Objects​

class TUpsertOptionsDict(TypedDict)

View source on GitHub

skip_unchanged_rows​

If True, dlt does not update destination records that equal their loaded record. Defaults to False.

row_version_column_name​

Column that changes when a record changes. With skip_unchanged_rows, dlt compares only this column to detect changed records.

TReferenceCardinality​

Represents cardinality between column (left) and referenced_column (right)

Note that cardinality is not symmetric. For example:

  • Author, 0 to many, Book an author can have 0 to many book
  • Book, 1 to 1, Author a book must have exactly 1 author

The statement (Author, 0 to many, Book) doesn't imply (Book, many to 0, Author).

_TTableReferenceBase Objects​

class _TTableReferenceBase(TypedDict)

View source on GitHub

Describes a reference to another table's columns. columns corresponds to the referenced_columns in the referenced table and their order should match.

label​

Text providing semantic information about the reference.

For example, the label "liked" describe the relationship between user and post (user.id, "liked", post.id)

cardinality​

Cardinality of the relationship between table.column (left) and referenced_table.referenced_column (right).

columns​

Name of the column(s) from table

referenced_table​

Name of the referenced table

referenced_columns​

Name of the columns(s) from referenced_table

TTableReferenceInline Objects​

class TTableReferenceInline(_TTableReferenceBase, TypedDict)

View source on GitHub

table​

Name of the table. When TTableReference is defined on a TTableSchema (i.e., "inline reference"), the table value is determined by TTableSchema["name"]

TTableReferenceStandalone Objects​

class TTableReferenceStandalone(_TTableReferenceBase, TypedDict)

View source on GitHub

table​

Name of the table. When TTableReference is defined on a TTableSchema (i.e., "inline reference"), the table value is determined by TTableSchema["name"]

TTableSchema Objects​

class TTableSchema(_TTableSchemaBase)

View source on GitHub

TypedDict that defines properties of a table

TColumnDefaultHint​

Allows using not_null in default hints setting section

TStoredSchema Objects​

class TStoredSchema(TypedDict)

View source on GitHub

TypeDict defining the schema representation in storage

This demo works on codespaces. Codespaces is a development environment available for free to anyone with a Github account. You'll be asked to fork the demo repository and from there the README guides you with further steps.
The demo uses the Continue VSCode extension.

Off to codespaces!

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