JSON包括Object类型和Nested类型,查询 JSON Object类型时直接使用所需查询类型进行操作即可,查询JSON Nested类型时必须使用NestedQuery包装查询条件。
前提条件
已在数据表上创建多元索引并配置JSON字段的类型。
使用限制
向量类型字段无法在JSON中使用。
查询场景
假设数据表中有id(String类型)和address(String类型)列,其中address列用于存储JSON格式的数据。
假设某行address列值为[{ "country": "China", "city": "hangzhou" }, { "country": "usa", "city": "Seattle" }]。当查询条件为country="China"且city="Seattle"时,如果address列设置为Nested类型,则无法查到该行数据;如果address列设置为Object类型,则可以查询到该行数据。
示例代码
JSON Nested类型查询示例
以下示例用于查询address的同一子行能满足address.country为"China"且address.city为"Seattle"两个条件的行数据。
import (
"fmt"
"github.com/aliyun/aliyun-tablestore-go-sdk/tablestore"
"github.com/aliyun/aliyun-tablestore-go-sdk/tablestore/search"
)
func nestedQuery1(client *tablestore.TableStoreClient) {
searchRequest := &tablestore.SearchRequest{}
searchRequest.SetTableName("<TABLE_NAME>")
searchRequest.SetIndexName("<SEARCH_INDEX_NAME>")
// 查询条件一:address.country = "China"
termQuery1 := &search.TermQuery{
FieldName: "address.country",
Term: "China",
}
// 查询条件二:address.city = "Seattle"
termQuery2 := &search.TermQuery{
FieldName: "address.city",
Term: "Seattle",
}
// 组合两个条件:必须同时满足
boolQuery := &search.BoolQuery{
MustQueries: []search.Query{
termQuery1,
termQuery2,
},
}
// 嵌套查询
nestedQuery := &search.NestedQuery{
Path: "address",
Query: boolQuery,
ScoreMode: search.ScoreMode_None,
}
// 构建并执行搜索
searchQuery := search.NewSearchQuery()
searchQuery.SetQuery(nestedQuery)
searchRequest.SetSearchQuery(searchQuery)
resp, err := client.Search(searchRequest)
if err != nil {
fmt.Printf("Search failed: %v\n", err)
return
}
fmt.Printf("Found %d rows\n", len(resp.Rows))
for _, row := range resp.Rows {
fmt.Printf("Row: %+v\n", row.PrimaryKey)
}
}JSON Object类型查询示例
以下示例用于查询address列的多个子行满足address.country为"China"且address.city为"Seattle"两个条件的行数据。
import (
"fmt"
"github.com/aliyun/aliyun-tablestore-go-sdk/tablestore"
"github.com/aliyun/aliyun-tablestore-go-sdk/tablestore/search"
)
func boolQuery(client *tablestore.TableStoreClient) {
searchRequest := &tablestore.SearchRequest{}
searchRequest.SetTableName("<TABLE_NAME>")
searchRequest.SetIndexName("<SEARCH_INDEX_NAME>")
// 查询条件一:address.country = "China"
termQuery1 := &search.TermQuery{
FieldName: "address.country",
Term: "China",
}
//查询条件二:address.city = "Seattle"
termQuery2 := &search.TermQuery{
FieldName: "address.city",
Term: "Seattle",
}
// 通过 BoolQuery 的 Must 条件,查询同时满足上述条件的子行
// 组合两个条件:必须同时满足
boolQuery := &search.BoolQuery{
MustQueries: []search.Query{
termQuery1,
termQuery2,
},
}
// 构建并执行搜索
searchQuery := search.NewSearchQuery()
searchQuery.SetQuery(boolQuery)
searchRequest.SetSearchQuery(searchQuery)
// 执行搜索
resp, err := client.Search(searchRequest)
if err != nil {
fmt.Printf("Search failed: %v\n", err)
return
}
fmt.Printf("Found %d rows\n", len(resp.Rows))
for _, row := range resp.Rows {
fmt.Printf("Row: %+v\n", row.PrimaryKey)
}
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