(nil),access([t2.c2],[t2.c1]),partitions(p0),is_index_back=false,range_key([t2.c1]),range(4;MAX),range_cond([t2.c1>4])2-output([t1.c2],[t1.c1]),filter(nil),access([t1.c2],[t1.c1]),partitions(p0),is_index_back=false,range_key([t1.__pk_increment],[t1.__pk_...
EXPLAIN: {"query_block": {"select_id": 1,"cost_info": {"query_cost":"2.00"},"table": {"table_name":"tb_book","access_type":"ALL","rows_examined_per_scan": 5,"rows_produced_per_join": 5,"filtered":"100.00","cost_info": {"read_cost":"1.00","eval_cost":"1.00","prefix...
create database `explain_test` DEFAULT CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci; -- switch database use `explain_test`; -- --- -- table structure for `tb_book` -- --- DROP TABLE IF EXISTS `tb_book`; CREATE TABLE `tb_book` ( `book_id` int(11) NOT NULL,...
TiDB(root@127.0.0.1:test) > explain select /*+ STREAM_AGG() */ count(*) from t; +---+---+---+---+---+ | id | estRows | task | access object | operator info | +---+---+---+---+---
CREATEDATABASE dbTest;CREATETABLEtbPerson ( IdintPRIMARYKEY, LastNamevarchar(255), FirstNamevarchar(255), Addressvarchar(255), Cityvarchar(255) );CREATEINDEX id_tbTest_LastNameONtbPerson(LastName);INSERTINTOtbPersonvalues(1,'Li','Lei','Nanjing Road','Nanjing');INSERTINTOtbPersonvalues(2,'...
--projectUsed to rearrange columns and compute expressions, that is, project data. Result--Run scalar functions that don't involve any table access. --returnReturn rows to the leader or client. Subplan--Used for certain subqueries. UniqueuniqueEliminates duplicates from SELECT DISTINCT and UNION ...
To access explain plans for queries run on both main clusters, concurrency scaling clusters, and serverless namespaces, we recommend that you use the SYS monitoring view SYS_QUERY_EXPLAIN . The data in the SYS monitoring view is formatted to be easier to use and understand. Table columns ...
In cases where the convenience is not needed or the additional return fields are required, use the database command. Note Using explain ignores all existing plan cache entries and prevents the MongoDB query planner from creating a new plan cache entry....
为实现向后兼容,可以使用-d代替-database。 -useruser-idpassword 建立数据库连接时要使用的授权标识和密码。user-id和password都必须符合Db2®命名约定,并且必须可以由数据库识别。 为实现向后兼容,可以使用-u代替-user。 output-options: 这些选项指定db2expln输出所应定向到的位置。除非指定-help选项,否则必须至...
Using sequenced numbers ensures that an attacker can’t reuse or replay captured data to establish a session or gain information. Using sequenced numbers also protects against attempts to intercept a message and use it to access resources, possibly months later. Connection security rules You can ...