Skip to main content
Version: devel

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

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

DEFAULT_VALIDITY_COLUMN_NAMES

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

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!

DHelp

Ask a question

Welcome to "Codex Central", your next-gen help center, driven by OpenAI's GPT-4 model. It's more than just a forum or a FAQ hub – it's a dynamic knowledge base where coders can find AI-assisted solutions to their pressing problems. With GPT-4's powerful comprehension and predictive abilities, Codex Central provides instantaneous issue resolution, insightful debugging, and personalized guidance. Get your code running smoothly with the unparalleled support at Codex Central - coding help reimagined with AI prowess.