For a given table, retrieves the values from the requested column(s). Maps of column name to the array of values as well as the column data type are returned. This endpoint supports pagination with the input parameter offset and input parameter limit parameters.
Window functions, which can perform operations like moving averages, are available through this endpoint as well as GPUdb.create_projection().
When using pagination, if the table (or the underlying table in the case of a view) is modified (records are inserted, updated, or deleted) during a call to the endpoint, the records or values retrieved may differ between calls based on the type of the update, e.g., the contiguity across pages cannot be relied upon.
If input parameter table_name is empty, selection is performed against a single-row virtual table. This can be useful in executing temporal (NOW()), identity (USER()), or constant-based functions (GEODIST(-77.11, 38.88, -71.06, 42.36)).
The response is returned as a dynamic schema. For details see: dynamic schemas documentation.
Parameters
Name of the table or view on which this operation will be performed, in [schema_name.]table_name format, using standard name resolution rules. An empty table name retrieves one record from a single-row virtual table, where columns specified should be constants or constant expressions.
The list of column values to retrieve. The user can provide a single element (which will be automatically promoted to a list internally) or a list.
A positive integer indicating the number of initial results to skip (this can be useful for paging through the results). The default value is 0. The minimum allowed value is 0. The maximum allowed value is MAX_INT.
A positive integer indicating the maximum number of results to be returned, or END_OF_SET (-9999) to indicate that the maximum number of results allowed by the server should be returned. The number of records returned will never exceed the server’s own limit, defined by the max_get_records_size parameter in the server configuration. Use output parameter has_more_records to see if more records exist in the result to be fetched, and input parameter offset and input parameter limit to request subsequent pages of results. The default value is -9999.
Specifies the encoding for returned records; either binary or json. Allowed values are:
binary
json
The default value is ‘binary’.
Allowed keys are:
expression – Filter expression to apply to the table.
sort_by – Column that the data should be sorted by. Used in conjunction with sort_order. The order_by option can be used in lieu of sort_by / sort_order. The default value is ‘’.
sort_order – String indicating how the returned values should be sorted - ascending or descending. If sort_order is provided, sort_by has to be provided. Allowed values are:
ascending
descending
The default value is ‘ascending’.
order_by – Comma-separated list of the columns to be sorted by as well as the sort direction, e.g., ‘timestamp asc, x desc’. The default value is ‘’.
convert_wkts_to_wkbs – If true, then WKT string columns will be returned as WKB bytes. Allowed values are:
true
false
The default value is ‘false’.
route_to_tom – For multihead record retrieval without shard key expression - specifies from which tom to retrieve data.
The default value is an empty dict ( ).
Returns
A dict with the following entries–
The same table name as was passed in the parameter list.
Avro schema of output parameter binary_encoded_response or output parameter json_encoded_response.
Avro binary encoded response.
Avro JSON encoded response.
Total/Filtered number of records.
Too many records. Returned a partial set.
Additional information.
RecordType or None) –A RecordType object using which the user can decode the binary data by using GPUdbRecord.decode_binary_data(). If JSON encoding is used, then None.