/get/records/bycolumn

URL: http://GPUDB_IP_ADDRESS:GPUDB_PORT/get/records/bycolumn

For a given table, retrieves the values of the given columns within a given range. It returns maps of column name to the vector of values for each supported data type (double, float, long, int and string). This operation supports pagination feature, i.e. values that are retrieved are those associated with the indices between the start (offset) and end value (offset + limit) parameters (inclusive). If there are num_points values in the table then each of the indices between 0 and num_points-1 retrieves a unique value.

Note that when using the pagination feature, if the table (or the underlying table in case of a view) is updated (records are inserted, deleted or modified) the records or values retrieved may differ between calls (discontiguous or overlap) based on the type of the update.

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 this operation will be performed. The table cannot be a parent set.
column_names	array of strings	The list of column values to retrieve.
offset	long	A positive integer indicating the number of initial results to skip (this can be useful for paging through the results). The minimum allowed value is 0. The maximum allowed value is MAX_INT.
limit	long	A positive integer indicating the maximum number of results to be returned (if not provided the default is 10000), or END_OF_SET (-9999) to indicate that the maximum number of results allowed by the server should be returned.
encoding	string	Specifies the encoding for returned records; either 'binary' or 'json'. Default value is 'binary'. The allowed values are: binary json
options	map of strings	Default value is an empty map ( {} ). Supported Parameters (keys) Parameter Description expression Optional filter expression to apply to the table. sort_by Optional column that the data should be sorted by. Empty by default (i.e. no sorting is applied). sort_order String indicating how the returned values should be sorted - ascending or descending. Default is 'ascending'. If sort_order is provided, sort_by has to be provided. Default value is 'ascending'. The allowed values are: ascending descending 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 parameter column_names. If any alias is given for any column name, the alias must be used, rather than the original column name. Default value is ''.

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	'get_records_by_column_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 /get/records/bycolumn endpoint: Name Type Description table_name string The same table name as was passed in the parameter list. 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. Empty string in case of an error.