Version:

/aggregate/unpivot

URL: http://GPUDB_IP_ADDRESS:GPUDB_PORT/aggregate/unpivot

Rotate the column values into rows values.

For unpivot details and examples, see Unpivot. For limitations, see Unpivot Limitations.

Unpivot is used to normalize tables that are built for cross tabular reporting purposes. The unpivot operator rotates the column values for all the pivoted columns. A variable column, value column and all columns from the source table except the unpivot columns are projected into the result table. The variable column and value columns in the result table indicate the pivoted column name and values respectively.

The response is returned as a dynamic schema. For details see: dynamic schemas documentation.

Input Parameter Description

Name Type Description
table_name string Name of the table on which the operation will be performed. Must be an existing table/view.
column_names array of strings List of column names or expressions. A wildcard '*' can be used to include all the non-pivoted columns from the source table.
variable_column_name string Specifies the variable/parameter column name. The default value is ''.
value_column_name string Specifies the value column name. The default value is ''.
pivoted_columns array of strings List of one or more values typically the column names of the input table. All the columns in the source table must have the same data type.
encoding string

Specifies the encoding for returned records.

Supported Values Description
binary Indicates that the returned records should be binary encoded.
json Indicates that the returned records should be json encoded.
options map of string to strings

Optional parameters. The default value is an empty map ( {} ).

Supported Parameters (keys) Parameter Description
collection_name Name of a collection which is to contain the table specified in result_table. If the collection provided is non-existent, the collection will be automatically created. If empty, then the table will be a top-level table.
result_table The name of the table used to store the results. Has the same naming restrictions as tables. If present, no results are returned in the response.
result_table_persist

If true, then the result table specified in result_table will be persisted and will not expire unless a ttl is specified. If false, then the result table will be an in-memory table and will expire unless a ttl is specified otherwise. The supported values are:

  • true
  • false
expression Filter expression to apply to the table prior to unpivot processing.
order_by Comma-separated list of the columns to be sorted by; e.g. 'timestamp asc, x desc'. The columns specified must be present in input table. If any alias is given for any column name, the alias must be used, rather than the original column name. The default value is ''.
chunk_size Indicates the chunk size to be used for the result table. Must be used in combination with the result_table option.
limit The number of records to keep. The default value is ''.
ttl Sets the TTL of the table specified in result_table.
view_id view this result table is part of. The default value is ''.
materialize_on_gpu

If true then the output columns will be cached on the GPU. The supported values are:

  • true
  • false
create_indexes Comma-separated list of columns on which to create indexes on the table specified in result_table. The columns specified must be present in output column names. If any alias is given for any column name, the alias must be used, rather than the original column name.
result_table_force_replicated

Force the result table to be replicated (ignores any sharding). Must be used in combination with the result_table option. The supported values are:

  • true
  • false

Output Parameter Description

The GPUdb server embeds the endpoint response inside a standard response structure which contains status information and the actual response to the query. Here is a description of the various fields of the wrapper:

Name Type Description
status String 'OK' or 'ERROR'
message String Empty if success or an error message
data_type String 'aggregate_unpivot_request' or 'none' in case of an error
data String Empty string
data_str JSON or String

This embedded JSON represents the result of the /aggregate/unpivot endpoint:

Name Type Description
table_name string Typically shows the result-table name if provided in the request (Ignore otherwise).
response_schema_str string Avro schema of output parameter binary_encoded_response or output parameter json_encoded_response.
binary_encoded_response bytes Avro binary encoded response.
json_encoded_response string Avro JSON encoded response.
total_number_of_records long Total/Filtered number of records.
has_more_records boolean Too many records. Returned a partial set.
info map of string to strings Additional information.

Empty string in case of an error.