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Get Table From Key

Description

This functor retrieves the sub-table corresponding to the given chain of keys from a given input table.

Inputs

Name Type Description
Table Table The input table.
Keys Tuple Chain of keys identifying the sub-table that will be retrieved.

Outputs

Name Type Description
Result Table The resulting sub-table.

Group

Notes

This functor retrieves all elements corresponding to the given tuple of keys in the input table. For example, given the table below

Key1* Key2* Key3* Value1 Value2 Value3
1 “a” 11 12 “bbbb” 23
1 “b” 22 12 “cccc” 23
2 “a” 11 12 “bbbb” 14
2 “a” 22 12 “aaaa” 23
2 “d” 22 12 “dddd” 12

retrieving the sub-table corresponding to the tuple of keys <2, “a”>, where 2 corresponds to column “Key1” and “a” corresponds to column “Key2”,

Key1* Key2* Key3* Value1 Value2 Value3
1 “a” 11 12 “bbbb” 23
1 “b” 22 12 “cccc” 23
2 “a” 11 12 “bbbb” 14
2 “a” 22 12 “aaaa” 23
2 “d” 22 12 “dddd”

yelds

Key3* Value1 Value2 Value3
11 12 “bbbb” 14
22 12 “aaaa” 23

and retrieving the sub-table corresponding to the tuple of keys <2>, where 2 corresponds to column “Key1”,

Key1* Key2* Key3* Value1 Value2 Value3
1 “a” 11 12 “bbbb” 23
1 “b” 22 12 “cccc” 23
2 “a” 11 12 “bbbb” 14
2 “a” 22 12 “aaaa” 23
2 “d” 22 12 “dddd” 12

yelds

Key2* Key3* Value1 Value2 Value3
“a” 11 12 “bbbb” 14
“a” 22 12 “aaaa” 23
“d” 22 12 “dddd” 12

If the resulting sub-table does not have at least one column of keys or if the given tuple of keys is not present in the input table, an error is reported.

It is not possible to retrieve a sub-table indexed by keys from arbitrary key columns. For example, in the example above, it is not possible to retrieve a sub-table corresponding to keys <2, 22>, where 2 corresponds to the first column (“Key1”) and 22 corresponds to the third column (“Key3”). To do this, first reorder the key columns using the Reorder Table Columns functor.

Internal Name

GetTableFromKey