“FreeBSD:Apache”与“MySQL explain”:页面之间的差异

来自WHY42
(页面间差异)
imported>Riguz
(创建页面,内容为“<source lang="bash"> pkg install apache24 #/etc/rc.conf apache24_enable="yes" </source> Category:Linux/Unix”)
 
无编辑摘要
 
第1行: 第1行:
<source lang="bash">
<pre>
pkg install apache24
mysql> explain SELECT COUNT(*) FROM vehicle_prod WHERE fin LIKE '%00000' \G
*************************** 1. row ***************************
          id: 1
  select_type: SIMPLE
        table: vehicle_prod
  partitions: NULL
        type: index
possible_keys: NULL
          key: idx_vehicle_prod_fin
      key_len: 203
          ref: NULL
        rows: 3182812
    filtered: 11.11
        Extra: Using where; Using index
1 row in set, 1 warning (0.00 sec)
</pre>


#/etc/rc.conf
其中:
apache24_enable="yes"
*id select_id The SELECT identifier
</source>
*select_type None The SELECT type
 
*table table_name The table for the output row
 
*partitions partitions The matching partitions
[[Category:Linux/Unix]]
*type access_type The join type
*possible_keys possible_keys The possible indexes to choose
*key key The index actually chosen
*key_len key_length The length of the chosen key
*ref ref The columns compared to the index
*rows rows Estimate of rows to be examined
*filtered filtered Percentage of rows filtered by table condition
*Extra None Additional information
[[Category:Datebase]]

2018年9月18日 (二) 09:16的版本

mysql> explain SELECT COUNT(*) FROM vehicle_prod WHERE fin LIKE '%00000' \G
*************************** 1. row ***************************
           id: 1
  select_type: SIMPLE
        table: vehicle_prod
   partitions: NULL
         type: index
possible_keys: NULL
          key: idx_vehicle_prod_fin
      key_len: 203
          ref: NULL
         rows: 3182812
     filtered: 11.11
        Extra: Using where; Using index
1 row in set, 1 warning (0.00 sec)

其中:

  • id select_id The SELECT identifier
  • select_type None The SELECT type
  • table table_name The table for the output row
  • partitions partitions The matching partitions
  • type access_type The join type
  • possible_keys possible_keys The possible indexes to choose
  • key key The index actually chosen
  • key_len key_length The length of the chosen key
  • ref ref The columns compared to the index
  • rows rows Estimate of rows to be examined
  • filtered filtered Percentage of rows filtered by table condition
  • Extra None Additional information