cenos7 virubual box Add storage

 https://sam.liho.tw/2020/07/06/virtualbox-%E6%94%B9%E8%AE%8A-centos-7-%E7%A1%AC%E7%A2%9F%E5%A4%A7%E5%B0%8F-%E8%AE%8A%E5%A4%A7%E7%82%BA%E4%BE%8B/

mariadb command

 1. Show table schema

show create table TABLENAME;

describe TABLENAME;

2.  show db parameter

show status like '%max%';

3. show all table and databases;

show  tables;

show databases;

4. Show Indexs;

show indexes from TABLENAME;

ref 1

4.2 Index For Hash and B-Tree

https://dev.mysql.com/doc/refman/8.0/en/index-btree-hash.html

https://stackoverflow.com/questions/7306316/b-tree-vs-hash-table

4.3 Index type

https://mariadb.com/kb/en/getting-started-with-indexes/

5. Analysze sequence 

show table status where name = 'tablename';

explain select * from tablename where condition;

ref 1

6.  deadlock

https://blog.gslin.org/archives/2014/10/29/5226/mysql-innodb-%E9%81%87%E5%88%B0-deadlock-%E6%99%82%E7%9A%84%E5%88%A4%E8%AE%80/

https://t.codebug.vip/questions-776021.htm

7. maraidb foreigin key

select concat(fks.constraint_schema, '.', fks.table_name) as foreign_table, '->' as rel, concat(fks.unique_constraint_schema, '.', fks.referenced_table_name) as primary_table, fks.constraint_name, group_concat(kcu.column_name order by position_in_unique_constraint separator ', ') as fk_columns from information_schema.referential_constraints fks join information_schema.key_column_usage kcu on fks.constraint_schema = kcu.table_schema and fks.table_name = kcu.table_name and fks.constraint_name = kcu.constraint_name -- where fks.constraint_schema = 'database name' group by fks.constraint_schema, fks.table_name, fks.unique_constraint_schema, fks.referenced_table_name, fks.constraint_name order by fks.constraint_schema, fks.table_name;

https://dataedo.com/kb/query/mariadb/list-foreign-keys

8. Look the priviledge

SHOW GRANTS;

https://dba.stackexchange.com/questions/63404/how-to-grant-super-privilege-to-the-user

9. Bin Log

https://kknews.cc/zh-tw/code/8vx9vbn.html

https://www.tw511.com/18/139/4051.html

http://benjr.tw/102425

10. Foregin key problem

https://www.cnblogs.com/shishibuwan/p/10863347.html

video learning

 

[Media] 影音傳輸-基礎知識

https://pjchender.github.io/2019/06/24/media-%E5%BD%B1%E9%9F%B3%E5%82%B3%E8%BC%B8-%E5%9F%BA%E7%A4%8E%E7%9F%A5%E8%AD%98/

avinfo字段说明

https://wcs.chinanetcenter.com/document/API/Appendix/avinfo-description

FFmpeg install on centos 7 and learning

 

https://www.tecmint.com/install-ffmpeg-in-linux/

https://lnpcd.blogspot.com/2012/09/ffmpeg.html

https://opensource.com/article/17/6/ffmpeg-convert-media-file-formats

case sensitivity in MySQL and MariaDB queries

 

#

https://mariadb.com/kb/en/insert-ignore/

#

https://mariadb.com/kb/en/supported-character-sets-and-collations/

#

https://uiop7890.pixnet.net/blog/post/22885702-%5B%E5%8E%9F%E5%89%B5%5D-utf8_unicode_ci-%E5%92%8C-utf8_bin-%E7%9A%84%E5%B7%AE%E7%95%B0

#

https://mariadb.com/kb/en/setting-character-sets-and-collations/

# office

https://mariadb.com/kb/en/setting-character-sets-and-collations/

# mb4

https://khiav223577.github.io/blog/2019/06/30/MySQL-%E7%B7%A8%E7%A2%BC%E6%8C%91%E9%81%B8%E8%88%87%E5%B7%AE%E7%95%B0%E6%AF%94%E8%BC%83/ 

#

https://exp.uniuni.space/she-ding-mariadb-bian-ma.html

#

https://federico-razzoli.com/case-sensitivity-in-mysql-and-mariadb-queries