You can use match all query to match all rows in a table to query the total number of rows in the table and return multiple random rows.
Prerequisites
- The OTSClient is initialized. For more information, see Initialization.
- A data table is created. Data is written to the table.
- A search index is created for the data table. For more information, see Create search indexes.
Parameters
Parameter | Description |
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query | The query type. To use match all query, set this parameter to MatchAllQuery. |
table_name | The name of the table. |
index_name | The name of the search index. |
limit | The maximum number of rows that the current query returns. To query the number of matched rows without detailed data, you can set limit to 0. In this case, Tablestore returns the number of matched rows without data from the table. |
get_total_count | Specifies whether to return the total number of rows that match the query conditions. By default, this parameter is set to false, which indicates that the total number of rows that match the query conditions is not returned. Query performance is affected when this parameter is set to true. |
columns_to_get | Specifies whether to return all columns of each matched row.
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Examples
Use match all query to query the total number of rows in the table.
- Perform match all query by using Tablestore SDK for Python V5.2.1 or laterBy default, if you use Tablestore SDK for Python V5.2.1 or later to perform a match all query, SearchResponse objects are returned. The following code provides a request sample:
query = MatchAllQuery() all_rows = [] next_token = None first_page = True while first_page or next_token: search_response = client.search(table_name, index_name, SearchQuery(query, next_token=next_token, limit=100, get_total_count=True), columns_to_get=ColumnsToGet(['k', 't', 'g', 'ka', 'la'], ColumnReturnType.SPECIFIED)) all_rows.extend(search_response.rows) first_page = False for row in all_rows: print row print 'Total rows:', len(all_rows)
You can use the following sample request to return results of the Tuple type:query = MatchAllQuery() all_rows = [] next_token = None first_page = True while first_page or next_token: rows, next_token, total_count, is_all_succeed, agg_results, group_by_results = client.search(table_name, index_name, SearchQuery(query, next_token=next_token, limit=100, get_total_count=True), columns_to_get=ColumnsToGet(['k', 't', 'g', 'ka', 'la'], ColumnReturnType.SPECIFIED)).v1_response() all_rows.extend(rows) first_page = False for row in all_rows: print row print 'Total rows:', len(all_rows)
- Perform match all query by using Tablestore SDK for Python of a version earlier than 5.2.1
By default, if you use Tablestore SDK for Python of a version earlier than 5.2.1 to perform a match all query, results of the Tuple type are returned. The following code provides a request sample:
query = MatchAllQuery() all_rows = [] next_token = None first_page = True while first_page or next_token: rows, next_token, total_count, is_all_succeed = client.search(table_name, index_name, SearchQuery(query, next_token=next_token, limit=100, get_total_count=True), columns_to_get=ColumnsToGet(['k', 't', 'g', 'ka', 'la'], ColumnReturnType.SPECIFIED)) all_rows.extend(rows) first_page = False for row in all_rows: print row print 'Total rows:', len(all_rows)