Skip to main content
Version: Python

from_constituent_tables

from_constituent_tables is a PartitionedTable method that creates a new PartitionedTable with a single column named __CONSTITUENT__, containing the provided constituent tables. The resultant partitioned table has no key columns, and its unique_keys and constituent_changes_permitted are False. It is a PartitionedTable class method, meaning it can be called on an instance of the class or the class itself.

Syntax​

PartitionedTable.from_constituent_tables(
  tables: List[Table],
  constituent_table_columns: List[Column]
) -> PartitionedTable

Parameters​

ParameterTypeDescription
tablesList[Table]

The constituent tables.

constituent_table_columnsList[Column]

A list of column definitions compatible with all the constituent tables. Default is None. When constituent_table_columns is not provided, it will be set to the column definitions of the first table in the provided constituent tables.

Returns​

A PartitionedTable with a single column named __CONSTITUENT__, containing the provided constituent tables. The resulting PartitionedTable has no key columns, and both its unique_keys and constituent_changes_permitted properties are set to False.

Example​

The following example uses from_constituent_tables to construct a partitioned table with no key columns.

from deephaven.table import PartitionedTable
from deephaven import empty_table

source1 = empty_table(5).update(["X = i", "Y = (i % 2 == 0) ? `A` : `B`"])
source2 = empty_table(5).update(["X = i + 2", "Y = (i % 3 == 1) ? `C` : `B`"])

pt = PartitionedTable.from_constituent_tables(tables=[source1, source2])
result = pt.table