URL: http://GPUDB_IP_ADDRESS:GPUDB_PORT/get/records/bycolumn
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 /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.
The response is returned as a dynamic schema. For details see: dynamic schemas documentation.
Name | Type | Description | ||||||||||||
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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'. The supported values are:
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options | map of string to strings | The default value is an empty map ( {} ).
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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 | |||||||||||||||||||||
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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:
Empty string in case of an error. |