JSON queries - Tablestore SDK for Python - Tablestore - Alibaba Cloud Documentation Center

Prerequisites

Install the Tablestore SDK for Python and initialize a client.

The target field is configured as an Object or Nested JSON field in the search index. For more information, see Create a search index.

Description

JSON queries do not have a dedicated query type. Select a query method based on the json_type of the JSON field in the search index.

JSON type	Description
Object	Does not preserve child-object boundaries in an array. Directly use a query type appropriate for the child-field type and matching requirement, and specify the full child-field path. Different conditions can be satisfied by different child objects.
Nested	Treats each child object in an array as an independent child row and preserves field relationships. Wrap child queries in `NestedQuery` and specify the Nested field path in `path`. All inner conditions must be satisfied by the same child row.

For example, assume the address array contains {"country":"China","city":"hangzhou"} and {"country":"usa","city":"Seattle"}. A query for both country=China and city=Seattle matches the row when the field is Object, but does not match it when the field is Nested.

Note

Child fields of a JSON field cannot be Vector fields.

Query an Object field

The following example queries rows in which profile.name is alice and profile.score is greater than or equal to 80.

query = BoolQuery(
    must_queries=[
        TermQuery("profile.name", "alice"),
        RangeQuery("profile.score", range_from=80),
    ]
)
response = client.search(
    "example_table",
    "example_index",
    SearchQuery(query, limit=10),
)
print(response.rows)

Query a Nested field

The following example requires the same child object in address to have address.country equal to China and address.city equal to Seattle. For other configurations, see Nested query.

child_query = BoolQuery(
    must_queries=[
        TermQuery("address.country", "China"),
        TermQuery("address.city", "Seattle"),
    ]
)
query = NestedQuery("address", child_query)
response = client.search(
    "example_table",
    "example_index",
    SearchQuery(query, limit=10),
)
print(response.rows)

Parameters

Search request

The search method contains the following parameters.

Name	Type	Description
table_name (required)	`str`	The name of the data table.
index_name (required)	`str`	The name of the search index.
search_query (required)	`SearchQuery`	The query condition and common query configurations.
columns_to_get (optional)	`ColumnsToGet`	The return column configuration. If this parameter is not specified, only primary key columns are returned.
routing_keys (optional)	`list`	The primary key values of custom routing fields. This parameter is not required if custom routing is not configured.
timeout_s (optional)	`int`	The request timeout in seconds. If this parameter is not specified, the client-level timeout is used.

Query configuration

search_query is of the SearchQuery type and contains the following parameters.

Name	Type	Description
query (required)	`Query`	For an Object field, specify a query appropriate for the child-field type. For a Nested field, specify `NestedQuery`.
sort (optional)	`Sort`	The sort order of results. For more information, see Sort and paginate results.
get_total_count (optional)	`bool`	Specifies whether to return the total number of matching rows. Default value: `False`. Setting this parameter to `True` increases query overhead.
next_token (optional)	`bytes`	The pagination token. Pass `next_token` from the previous response to retrieve the next page.
offset (optional)	`int`	The offset from which the query starts. Use this parameter for shallow pagination.
limit (optional)	`int`	The maximum number of rows to return. If this parameter is set to `0`, no rows are returned.
aggs (optional)	`list[Agg]`	The metric aggregation configurations. For more information, see Aggregation.
group_bys (optional)	`list[BaseGroupBy]`	The grouping configurations. For more information, see Aggregation.
collapse_field (optional)	`Collapse`	The result collapse configuration. For more information, see Collapse query results.
highlight (optional)	`Highlight`	The summary and highlighting configuration for `Text` fields. For more information, see Summary and highlighting.

Return columns

columns_to_get is of the ColumnsToGet type and contains the following parameters.

Name	Type	Description
column_names (optional)	`list[str]`	The names of attribute columns to return. Specify this parameter only when `return_type` is `SPECIFIED`.
return_type (optional)	`ColumnReturnType`	The return column mode. `NONE` (default) returns only primary key columns; `SPECIFIED` returns specified attribute columns; `ALL` returns all attribute columns in the table; and `ALL_FROM_INDEX` returns all stored fields in the index.

Response

The search method returns SearchResponse. The following table describes the core fields.

Field	Type	Description
rows	`list[Row]`	The rows returned by the query. The number does not exceed `limit`.
next_token	`bytes`	The token for the next page. An empty value indicates that no more data is available.
total_count	`int`	The number of matching rows. The value depends on `get_total_count`.
is_all_succeed	`bool`	Indicates whether all index partitions were queried. If the value is `False`, partial results are returned.
agg_results	`list[AggResult]`	The metric aggregation results. This field is empty if `aggs` is not configured.
group_by_results	`list[GroupByResult]`	The grouping results. This field is empty if `group_bys` is not configured.
search_hits	`list[SearchHit]`	The search hits, including extended information such as rows, relevance scores, and highlights.

Tuple-compatible response

Starting from Tablestore SDK for Python 5.2.0, search APIs return response objects instead of tuples. Version 5.1.0 and earlier return tuples directly. In version 5.2.1 and later, you can call SearchResponse.v1_response() to obtain a tuple compatible with earlier versions. For new code, access SearchResponse attributes directly to avoid unpacking errors if response fields are extended.

(
    rows,
    next_token,
    total_count,
    is_all_succeed,
    agg_results,
    group_by_results,
    search_hits,
) = response.v1_response()