XML Tutorials - Herong's Tutorial Examples
This XML tutorial book is a collection of notes and sample codes written by the author while he was learning XML himself. Topics include introduction to XML, DTD (Document Type Definition), XSD (XML Schema Definition), XPath (XML Path Language), XSL (Extensible Stylesheet Language), XSLT (XSL Transf... 2023-03-09, 11946🔥, 3💬
MySQL Tutorials - Herong's Tutorial Examples
This MySQL tutorial book is a collection of notes and sample codes written by the author while he was learning MySQL himself, an ideal tutorial guide for beginners. Topics include introduction of Structured Query Language (SQL); installation of MySQL server on Windows, Linux, and macOS; using MySQL ... 2022-11-22, 1065🔥, 1💬
"Multiple files found for the same tablespace ID" Error
This section provides a tutorial example on the 'Multiple files found for the same tablespace ID' error caused by an outdated database file left from an external MySQL server. 2022-10-01, 2354🔥, 0💬
MySQL Data Directory Initialization
Tutorial example on how to initialize the MySQL server data directory with the 'mysqld --initialize-insecure' command, which will create a root user without password. 2022-10-01, 913🔥, 0💬
--secure-file-priv="" - MySQL Server Option
This section provides a tutorial example on how to change the '--secure-file-priv' MySQL Server option, to control directory permissions for dumping all tables in a database as tab delimited files. 2022-10-01, 669🔥, 0💬
Impact of InnoDB Log Buffer on INSERT
This section provides a tutorial example to demonstrate the performance impact of InnoDB Log Buffer. Setting innodb_flush_log_at_trx_commit =0can reduce execution time reduction on INSERT and other data change statements from 35 ms to 1 ms. 2022-10-01, 598🔥, 0💬
"SELECT COUNT(*)" on InnoDB Table
This section provides a tutorial example showing why 'SELECT COUNT(*)' is slow on InnoDB tables. It does a full table scan by reading all data pages to count the number of rows. 2022-10-01, 430🔥, 0💬
MySQL Authentication Method "caching_sha2_password"
A tutorial example is provided on how to create a new user account with 'mysql_native_password' authentication method to avoid the 'caching_sha2_password' error with mysqli_connect() method. 2022-10-01, 324🔥, 0💬
Using DDL to Create Tables and Indexes
This chapter provides tutorial notes on DDL (Data Definition Language) statements. Topics include CREATE TABLE, CREATE INDEX, and ALTER TABLE statements; selecting column options when creating tables. 2022-10-01, 302🔥, 0💬
Transaction Management and Isolation Levels
This chapter provides tutorial notes on transactions. Topics include introduction of transactions, transaction management in MySQL, transaction isolation levels: Read Uncommitted, Read Committed, Repeatable Read, Serializable. 2022-10-01, 269🔥, 0💬
PHP mysqli_connect() Error on "localhost" on macOS
This section provides a tutorial on the PHP mysqli_connect() 'No such file or directory' error, and the workaround of replacing 'localhost' with '127.0.0.1'. 2022-10-01, 260🔥, 0💬
"SHOW PROFILE" - Query Profiling
This section provides a tutorial example on how to use the Query Profiling tool provided in MySQL server to figure out which steps of a query statement taking more execution time than others. 2022-10-01, 251🔥, 0💬
MySQL Command Line Client Tool
A tutorial example on how to use the MySQL Command Line Client Tool to connect to MySQL Server. The example also includes SQL commands to create a new test database/table and insert some data to the table. 2022-10-01, 237🔥, 0💬
Using "mysql" Command to Run SQL Statements
This section provides some tutorial examples on how to run SQL statements on a MySQL server with the client tool mysql. SQL statements can be executed one by one interactively, or in batch mode. 2022-10-01, 209🔥, 0💬
This section describes the third zodiac sign, Gemini, the Twins.
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