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 | ||||||||||
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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'. Default value is 'binary'. The allowed values are:
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options | map of strings | Default value is an empty map ( {} ).
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Output Parameter Description
Name | Type | Description |
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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. |