EXPLAIN returns a row of information for each table used in the SELECT statement. It lists the tables in the output in the order that MySQL would read them while processing the statement. MySQL resolves all joins using a nested-loop join method. This means that MySQL reads a row from the...
The partitions from which records would be matched by the query. The value is NULL for nonpartitioned tables. See Section 26.3.5, “Obtaining Information About Partitions”. type (JSON name: access_type) The join type. For descriptions of the different types, see EXPLAIN Join Types. pos...
EXPLAIN returnsa row of information for each table used in the SELECT statement. It lists thetables in the output in the order that MySQL would read them while processingthe statement. MySQL resolves all joins using a nested-loop join method. Thismeans that MySQL reads a row from the first ...
--显示这一步所访问的数据库中的表的名称 2.1.4 type The join type.For descriptions of the different types, see EXPLAIN Join Types. --对表所使用的访问方式。 2.1.5 possible_keys Thepossible_keys column indicates which indexes MySQL can choose from use to findthe rows in this table. Note ...
Step-by-Step Solution:1. Introduction to Nerve Fibers: Nerve fibers are classified based on their diameter, conduction velocity, and myelination. The primary types of nerve fibers are classified into three
rows: the estimated number of rows returned by an operator. If the value of the rows parameter is significantly different from the actual number of returned rows, the table statistics may not be updated. In this case, we recommend that you execute the analyze statement to update the table...
This tableis referenced as the child of table in a join that can be pushed down to the NDBkernel. Applies only in MySQL Cluster, when pushed-down joins are enabled. Seethe description of the ndb_join_pushdown serversystem variable for more information and examples. ...
When external users participate in meetings or chats hosted by your organization, the retention of these messages depends on the type of account they use:Guest accounts: If an external user joins using a guest account in your tenant, any messages they send are stored in both your users...
The openCypher explain feature is a feature that helps users to understand how the query is executed. Usually this is used in the context of query performance analysis. To invoke explain , you can pass the explain-mode parameter to an ExecuteQuery reques
Cause: The capability in question is not supported when the materialized view uses these types of joins. Action: Re-phrase the query to avoid the use of these types of joins. QSM-02113 expression in select list references multiple tables or views Cause: The capability in question is not su...