mysql>EXPLAINSELECTp.*->FROMparent p->WHEREp.idNOTIN(SELECTc.parent_idFROMchild c)\G***1. row***id:1selecttype:PRIMARYtable: p type:ALLpossible_keys:NULLkey:NULLkey_len:NULLref:NULLrows:160Extra: Usingwhere***2. row***id:2select_type: DEPENDENT SUBQUERYtable: c type: index_subque...
复制 mysql> SHOW SESSION STATUSLIKE'Handler_read%';+---+---+| Variable_name | Value |+---+---+| Handler_read_first | 0 || Handler_read_key | 0 || Handler_read_last | 0 || Handler_read_next | 0 || Handler_read_prev | 0 || Handler_read_rnd | 0 || Handler_read_rnd_...
-> FROM (SELECT id FROM users WHERE first = ‘west’) c; 4. DEPENDENT SUBQUERY 这个select-type 值是为使用子查询而定义的。下面的SQL语句提供了这个值: mysql> EXPLAIN SELECT p.* -> FROM parent p -> WHERE p.id NOT IN (SELECT c.parent_id FROM child c); 5. UNION 这是UNION 语句其中...
In MySQL 9.3, the default output format used by EXPLAIN (that is, when it has no FORMAT option) is determined by the value of the explain_format system variable. The precise effects of this variable are described later in this section. MySQL 9.3 supports an additional INTO option with EXP...
可以参考MySQL Reference Manual 获得更多信息:http://dev.mysql.com/doc/refman/5.5/en/explain-output.html。 2.1 key key 列指出优化器选择使用的索引。一般来说SQL 查询中的每个表都仅使用一个索引。也存在索引合并的少数例外情况,如给定表上用到了两个或者更多索引。
Using REVEL as our reference pathogenicity prediction tool and this variant yielding a REVEL score of 0.96 we can use the PP3 criterion at strong level according to Pejaver et al. (46) (see also Figure 1A–C). Open in new tabDownload slide...
In the case of Random Forest instead, a measure of absolute relevance, namely the feature importance, is attributed to each variable as a means to quantify its impact in the class prediction procedure. Although it is not directly employed for inference by the model (as is the case of the ...
Explain the concept of Array of Pointer and Pointer to Pointer in C programming - Array Of PointersJust like any other data type, we can also declare a pointer array.Declarationdatatype *pointername [size];For example, int *p[5]; //It represents an array
Adding this project as a reference would cause a circular dependency. adding values from c# to existing xml file Adding/Subtracting/Multiplying positive and negative numbers AdditionalFiles on Csproj files Address of a string variable(object) in C#? AdomdConnectionException This is usually a tempora...
For example, when the SQL statement contains bind variables the plan shown from using EXPLAIN PLAN ignores the bind variable values while the plan shown in V$SQL_PLAN takes the bind variable values into account in the plan generation process. It is easy to display an execution plan using the...