You can perform a range query to query data that falls within the specified range. If the type of the column is TEXT, Tablestore tokenizes the string and uses the tokens to match the keyword. A row meets the query conditions when at least one of the tokens in the row matches the query range.
Prerequisites
A TableStoreClient instance is initialized. For more information, see Initialize an OTSClient instance.
A data table is created and data is written to the data table. For more information, see Create a data table and Write data.
A search index is created for the data table. For more information, see Create a search index.
Parameters
Parameter | Description |
field_name | The name of the column that you want to query. |
range_from | The value from which the query starts. |
range_to | The value at which the query ends. |
include_lower | Specifies whether to include the value of the range_from parameter in the response. The value of this parameter is of the Boolean type. |
include_upper | Specifies whether to include the value of the range_to parameter in the response. The value of this parameter is of the Boolean type. |
table_name | The name of the data table. |
index_name | The name of the search index. |
query | The type of the query. Set this parameter to RangeQuery. |
limit | The maximum number of rows that you want the current query to return. To query only the number of rows that meet the query conditions without querying specific data of the rows, set the limit parameter to 0. |
get_total_count | Specifies whether to return the total number of rows that meet the query conditions. The default value is false, which indicates that the total number of rows that meet the query conditions is not returned. If you set this parameter to true, the query performance is compromised. |
columns_to_get | Specifies whether to return all columns of each row that meets the query conditions. You can specify the return_type and column_names fields for this parameter.
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Examples
The following examples show how to query the rows in which the value of the Col_Keyword column is between 'key100' and 'key200'.
Perform a range query by using Tablestore SDK for Python V5.2.1 or later
If you use Tablestore SDK for Python V5.2.1 or later to perform a range query, a SearchResponse object is returned by default. The following code provides a sample request:
query = RangeQuery('Col_Keyword', 'key100', 'key200', include_lower=False, include_upper=False) search_response = client.search( '<TABLE_NAME>', '<SEARCH_INDEX_NAME>', SearchQuery(query, limit=100, get_total_count=True), ColumnsToGet(return_type=ColumnReturnType.ALL) ) print('request_id : %s' % search_response.request_id) print('is_all_succeed : %s' % search_response.is_all_succeed) print('total_count : %s' % search_response.total_count) print('rows : %s' % search_response.rows) # # If deep paging is required, we recommend that you use the next_token parameter because this method has no limits on the paging depth. # all_rows = [] # next_token = None # # first round # search_response = client.search( # '<TABLE_NAME>', '<SEARCH_INDEX_NAME>', # SearchQuery(query, next_token=next_token, limit=100, get_total_count=True), # columns_to_get=ColumnsToGet(return_type=ColumnReturnType.ALL)) # all_rows.extend(search_response.rows) # # # loop # while search_response.next_token: # search_response = client.search( # '<TABLE_NAME>', '<SEARCH_INDEX_NAME>', # SearchQuery(query, next_token=search_response.next_token, limit=100, get_total_count=True), # columns_to_get=ColumnsToGet(return_type=ColumnReturnType.ALL)) # all_rows.extend(search_response.rows) # print('Total rows:%s' % len(all_rows))You can use the following sample request to return results of the Tuple type:
query = RangeQuery('Col_Keyword', 'key100', 'key200', include_lower=False, include_upper=False) rows, next_token, total_count, is_all_succeed, agg_results, group_by_results = client.search( '<TABLE_NAME>', '<SEARCH_INDEX_NAME>', SearchQuery(query, limit=100, get_total_count=True), ColumnsToGet(return_type=ColumnReturnType.ALL) ).v1_response()Perform a range query by using Tablestore SDK for Python of a version earlier than 5.2.1
If you use a version of Tablestore SDK for Python that is earlier than 5.2.1 to perform a range query, results of the TUPLE type are returned by default. The following sample code provides a sample request:
query = RangeQuery('Col_Keyword', 'key100', 'key200', include_lower=False, include_upper=False) rows, next_token, total_count, is_all_succeed = client.search( '<TABLE_NAME>', '<SEARCH_INDEX_NAME>', SearchQuery(query, limit=100, get_total_count=True), ColumnsToGet(return_type=ColumnReturnType.ALL) )
FAQ
References
When you use a search index to query data, you can use the following query methods: term query, terms query, match all query, match query, match phrase query, prefix query, range query, wildcard query, geo query, Boolean query, KNN vector query, nested query, and exists query. You can use the query methods provided by the search index to query data from multiple dimensions based on your business requirements.
You can sort or paginate rows that meet the query conditions by using the sorting and paging features. For more information, see Sorting and paging.
You can use the collapse (distinct) feature to collapse the result set based on a specific column. This way, data of the specified type appears only once in the query results. For more information, see Collapse (distinct).
If you want to analyze data in a data table, you can use the aggregation feature of the Search operation or execute SQL statements. For example, you can obtain the minimum and maximum values, sum, and total number of rows. For more information, see Aggregation and SQL query.
If you want to obtain all rows that meet the query conditions without the need to sort the rows, you can call the ParallelScan and ComputeSplits operations to use the parallel scan feature. For more information, see Parallel scan.