MariaDB 查看running queries,转换存储引擎，导出为HTML,XML

MariaDB 查看running queries,

转换存储引擎，导出为HTML,XML

先导入示例数据库http://www.isfdb.org/wiki/index.php/ISFDB_Downloads

wget http://isfdb.s3.amazonaws.com/backups/backup-MySQL-55-2016-03-26.zip

unzip backup-MySQL-55-2016-03-26.zip

CREATE DATABASE isfdb CHARACTER SET utf8;

mysql -ujlive -p isfdb

查看running queries

1.模拟一个非常慢的查询 

ALTER TABLE title_relationships DROP KEY titles;

SELECT titles.title_id AS ID,

titles.title_title AS Title,

authors.author_legalname AS Name,

(SELECT COUNT(DISTINCT title_relationships.review_id) FROM title_relationships

        WHERE title_relationships.title_id = titles.title_id) AS reviews

FROM  titles,authors,canonical_author

WHERE

        (SELECT COUNT(DISTINCT title_relationships.review_id) FROM title_relationships

                WHERE title_relationships.title_id = titles.title_id)>=10

        AND canonical_author.author_id = authors.author_id

        AND canonical_author.title_id=titles.title_id

        AND titles.title_parent=0 ;

说明：数据量太大时可以通过LIMIT ROWS EXAMINED语句定义查询长度以节省资源，如，在上面的查询语句后加上

LIMIT ROWS EXAMINED 10000;

还可以在查询长度的基础上限制输入长度

LIMIT 100 ROWS EXAMINED 10000;

2.在PROCESSLIST中查找查询时长超过60秒的ID,QUERY_ID

(jlive)[isfdb]>SELECT INFO, TIME, ID, QUERY_ID  FROM INFORMATION_SCHEMA.PROCESSLIST  WHERE TIME > 60 LIMIT 2G

*************************** 1. row ***************************

    INFO: SELECT titles.title_id AS ID,

titles.title_title AS Title,

authors.author_legalname AS Name,

(SELECT COUNT(DISTINCT title_relationships.review_id) FROM title_relationships

        WHERE title_relationships.title_id = titles.title_id) AS reviews

FROM  titles,authors,canonical_author

WHERE

        (SELECT COUNT(DISTINCT title_relationships.review_id) FROM title_relationships

                WHERE title_relationships.title_id = titles.title_id)>=10

        AND canonical_author.author_id = authors.author_id

        AND canonical_author.title_id=titles.title_id

        AND titles.title_parent=0

    TIME: 632

      ID: 30

QUERY_ID: 1483

*************************** 2. row ***************************

    INFO: NULL

    TIME: 860

      ID: 28

QUERY_ID: 103

3.查看对应查询ID的附加信息

(jlive)[isfdb]>SHOW EXPLAIN FOR 30;

+------+--------------------+---------------------+--------+-------------------+---------+---------+---------------------------------+--------+-------------+

| id   | select_type        | table               | type   | possible_keys     | key     | key_len | ref                             | rows   | Extra       |

+------+--------------------+---------------------+--------+-------------------+---------+---------+---------------------------------+--------+-------------+

|    1 | PRIMARY            | authors             | ALL    | PRIMARY           | NULL    | NULL    | NULL                            | 136889 |             |

|    1 | PRIMARY            | canonical_author    | ref    | titles,authors    | authors | 5       | isfdb.authors.author_id         |     10 | Using where |

|    1 | PRIMARY            | titles              | eq_ref | PRIMARY,parent_id | PRIMARY | 4       | isfdb.canonical_author.title_id |      1 | Using where |

|    3 | DEPENDENT SUBQUERY | title_relationships | ALL    | NULL              | NULL    | NULL    | NULL                            |  94824 | Using where |

|    2 | DEPENDENT SUBQUERY | title_relationships | ALL    | NULL              | NULL    | NULL    | NULL                            |  94824 | Using where |

+------+--------------------+---------------------+--------+-------------------+---------+---------+---------------------------------+--------+-------------+

5 rows in set, 1 warning (0.00 sec)

4.KILL掉该查询进程

(jlive)[isfdb]>KILL QUERY ID 1483;

Query OK, 0 rows affected (0.00 sec)

5.还原KEY

(jlive)[isfdb]>ALTER TABLE title_relationships ADD KEY titles (title_id);

Query OK, 94824 rows affected (0.26 sec)

Records: 94824  Duplicates: 0  Warnings: 0

(jlive)[isfdb]>SHOW WARNINGS;

Empty set (0.00 sec)

转换存储引擎

安装Cassandra存储引擎

INSTALL SONAME 'ha_cassandra';

或者

INSTALL PLUGIN Cassandra SONAME 'ha_cassandra';

SHOW PLUGINS;

SHOW STORAGE ENGINES;

卸载Cassandra

UNINSTALL SONAME 'ha_cassandra';

说明:mariadb-10.1的进抽包里默认没带cassandra的插件，这里先跳过

迁移表从MyISAM到Aria

(jlive)[isfdb]>SHOW TABLE STATUS LIKE 'authors'G

*************************** 1. row ***************************

           Name: authors

         Engine: MyISAM

        Version: 10

     Row_format: Dynamic

           Rows: 136889

 Avg_row_length: 58

    Data_length: 7943084

Max_data_length: 281474976710655

   Index_length: 4631552

      Data_free: 0

 Auto_increment: 227591

    Create_time: 2016-04-02 20:36:39

    Update_time: 2016-04-02 20:36:40

     Check_time: 2016-04-02 20:36:40

      Collation: latin1_swedish_ci

       Checksum: NULL

 Create_options: 

        Comment: 

1 row in set (0.00 sec)

(jlive)[isfdb]>ALTER TABLE authors ENGINE=Aria;

Query OK, 136889 rows affected (0.98 sec)

Records: 136889  Duplicates: 0  Warnings: 0

(jlive)[isfdb]>SHOW TABLE STATUS LIKE 'authors'G

*************************** 1. row ***************************

           Name: authors

         Engine: Aria

        Version: 10

     Row_format: Page

           Rows: 136889

 Avg_row_length: 66

    Data_length: 9043968

Max_data_length: 17592186011648

   Index_length: 5128192

      Data_free: 0

 Auto_increment: 227591

    Create_time: 2016-04-04 19:50:13

    Update_time: 2016-04-04 19:50:14

     Check_time: 2016-04-04 19:50:14

      Collation: latin1_swedish_ci

       Checksum: NULL

 Create_options: 

        Comment: 

 

1 row in set (0.00 sec)

(jlive)[isfdb]>ALTER TABLE awards ENGINE=InnoDB;

Query OK, 38496 rows affected (0.35 sec)

Records: 38496  Duplicates: 0  Warnings: 0

(jlive)[isfdb]>SHOW TABLE STATUS LIKE 'awards'G

*************************** 1. row ***************************

           Name: awards

         Engine: InnoDB

        Version: 10

     Row_format: Compact

           Rows: 38265

 Avg_row_length: 123

    Data_length: 4734976

Max_data_length: 0

   Index_length: 3178496

      Data_free: 4194304

 Auto_increment: 45358

    Create_time: 2016-04-04 19:52:54

    Update_time: NULL

     Check_time: NULL

      Collation: latin1_swedish_ci

       Checksum: NULL

 Create_options: 

        Comment: 

 

1 row in set (0.00 sec)

表存储引擎转换实际上是两个步骤

1.用新的存储引擎创建一张和原表属性完全相同的新表，仅存储引擎不同，并把数据全部copy到新表

2.删除原表，并装新表的名字改为原表的名字

导出为HTML,XML

1.导出为HTML

echo "SELECT * FROM authors LIMIT 100;" >isfdb-001.sql

mysql --html isfdb < isfdb-001.sql >isfdb-001.html

或用tidy对html加工下，使输出的html更规范标准

mysql --html isfdb < isfdb-001.sql | tidy -q -i -o isfdb-001.html

2.导出为XML

mysql --xml isfdb < isfdb-001.sql >isfdb-001.xml