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error 18 at 0 depth lookup: self signed certificate

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I was trying to test SSL connection between MySQL client and server. For that I created SSL certificate and keys by following the MySQL documentation at: Creating SSL Certificates and Keys Using openssl After finishing up all the commands when I verify the certificates by using: openssl verify -CAfile ca.pem server-cert.pem client-cert.pem I got the following output: error 18 at 0 depth lookup : self signed certificate error server-cert.pem: verification failed client-cert.pem: OK  Reason : The Common Name value used for the server and client certificates/keys must each differ from the Common Name value used for the CA certificate. Otherwise, the certificate and key files will not work for servers compiled using OpenSSL. Solution : When OpenSSL prompts you for the Common Name for each certificate, use different names. Common Name (e.g. server FQDN or YOUR name) []: I used values as follows: CA Cert:  ssl-ca-cert Server Cert: ssl-ca-server-cert Client Cer...
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How to check fragmentation in MySQL tables

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MySQL tables, including MyISAM and InnoDB, two of the most common types, experience fragmentation as data is inserted, updated and deleted randomly. Fragmentation can leave large holes in your table, blocks which must be read when scanning the table. Optimizing your table can therefore make full table scans and range scans more efficient. We will mention how to check fragmentation in MySQL tables using SQL queries. USE < put_your_dbname_here > SELECT TABLE_NAME, CONCAT(ROUND(( data_length + index_length ) / ( 1024 * 1024 ), 2), 'M') TOTAL_SIZE, CONCAT(ROUND(( DATA_FREE ) / ( 1024 * 1024 ), 2), 'M') DATA_FREE FROM information_schema.TABLES where table_schema = database() and ROUND(( DATA_FREE ) / ( 1024 * 1024 ), 2) > 0.00 ORDER BY DATA_FREE DESC; SELECT TABLE_NAME, ROUND(((Data_length - (TABLE_ROWS * Avg_row_length))/Data_length) * 100, 2) FRAG_Percent FROM information_schema.TABLES where table_schema = database() and TABLE_ROWS > 0 ...
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ERROR 1846 (0A000): ALGORITHM=INPLACE is not supported. Reason: Cannot change column type INPLACE. Try ALGORITHM=COPY.

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In this article I want to share my investigation, where I face this issue in GCP (why specially mention, you will know at the end), and hope that it might save someone's else time. The MySQL GCP version is:  5.7.33-google-log . mysql> ALTER TABLE t_user CHANGE COLUMN UserPassword UserPassword varchar(255) NOT null, ALGORITHM=INPLACE, LOCK=NONE; ERROR 1846 (0A000): ALGORITHM=INPLACE is not supported. Reason: Cannot change column type INPLACE. Try ALGORITHM=COPY.   mysql> ALTER TABLE t_user CHANGE COLUMN UserPassword UserPassword varchar(70) NOT null, ALGORITHM=INPLACE, LOCK=NONE; Query OK, 0 rows affected (0.01 sec) Records: 0  Duplicates: 0  Warnings: 0 In MySQL, utf8 corresponds to 3 byte length per character, hence according to MySQL utf8 will change byte length around 85 characters. According to documentation: Extending VARCHAR column size ALT...
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