atoti.Session.create_table()

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Session.create_table(name, *, data_types=frozendict({}), default_values=frozendict({}), keys=frozenset({}), partitioning=None)

• Parameters:
  • name (str) – The name of the table to create.
  • data_types (Mapping *[*ColumnName , DataType ]) – The table column names and their corresponding data type.
  • default_values (Mapping *[*ColumnName , Constant | None ]) – Mapping from column name to column default_value.
  • keys (AbstractSet *[*ColumnName ] | Sequence *[*ColumnName ]) – The columns that will become keys of the table. If a Set is given, the keys will be ordered as the table columns.
  • partitioning (str | None) – The definition of how the data will be split across partitions. Default rules:
    • Only non-joined tables are automatically partitioned.
    • Tables are automatically partitioned by hashing their key columns. If there are no key columns, all the dictionarized columns are hashed.
    • Joined tables can only use a sub-partitioning of the table referencing them.
    • Automatic partitioning is done modulo the number of available cores.
    For instance, "modulo4(country)" splits the data across 4 partitions based on the country column’s dictionarized value.
• Return type: Table

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Example

>>> from datetime import date
>>> table = session.create_table(
...     "Product",
...     data_types={
...         "Date": "LocalDate",
...         "Product": "String",
...         "Quantity": "double",
...     },
...     keys={"Product", "Date"},
... )
>>> table.head()
Empty DataFrame
Columns: [Quantity]
Index: []
>>> {column_name: table[column_name].data_type for column_name in table}
{'Date': 'LocalDate', 'Product': 'String', 'Quantity': 'double'}
>>> table.keys
('Date', 'Product')