- MySQL Basics
- MySQL - Home
- MySQL - Introduction
- MySQL - Features
- MySQL - Versions
- MySQL - Variables
- MySQL - Installation
- MySQL - Administration
- MySQL - PHP Syntax
- MySQL - Node.js Syntax
- MySQL - Java Syntax
- MySQL - Python Syntax
- MySQL - Connection
- MySQL - Workbench
- MySQL Databases
- MySQL - Create Database
- MySQL - Drop Database
- MySQL - Select Database
- MySQL - Show Database
- MySQL - Copy Database
- MySQL - Database Export
- MySQL - Database Import
- MySQL - Database Info
- MySQL Users
- MySQL - Create Users
- MySQL - Drop Users
- MySQL - Show Users
- MySQL - Change Password
- MySQL - Grant Privileges
- MySQL - Show Privileges
- MySQL - Revoke Privileges
- MySQL - Lock User Account
- MySQL - Unlock User Account
- MySQL Tables
- MySQL - Create Tables
- MySQL - Show Tables
- MySQL - Alter Tables
- MySQL - Rename Tables
- MySQL - Clone Tables
- MySQL - Truncate Tables
- MySQL - Temporary Tables
- MySQL - Repair Tables
- MySQL - Describe Tables
- MySQL - Add/Delete Columns
- MySQL - Show Columns
- MySQL - Rename Columns
- MySQL - Table Locking
- MySQL - Drop Tables
- MySQL - Derived Tables
- MySQL Queries
- MySQL - Queries
- MySQL - Constraints
- MySQL - Insert Query
- MySQL - Select Query
- MySQL - Update Query
- MySQL - Delete Query
- MySQL - Replace Query
- MySQL - Insert Ignore
- MySQL - Insert on Duplicate Key Update
- MySQL - Insert Into Select
- MySQL Indexes
- MySQL - Indexes
- MySQL - Create Index
- MySQL - Drop Index
- MySQL - Show Indexes
- MySQL - Unique Index
- MySQL - Clustered Index
- MySQL - Non-Clustered Index
- MySQL Operators and Clauses
- MySQL - Where Clause
- MySQL - Limit Clause
- MySQL - Distinct Clause
- MySQL - Order By Clause
- MySQL - Group By Clause
- MySQL - Having Clause
- MySQL - AND Operator
- MySQL - OR Operator
- MySQL - Like Operator
- MySQL - IN Operator
- MySQL - ANY Operator
- MySQL - EXISTS Operator
- MySQL - NOT Operator
- MySQL - NOT EQUAL Operator
- MySQL - IS NULL Operator
- MySQL - IS NOT NULL Operator
- MySQL - Between Operator
- MySQL - UNION Operator
- MySQL - UNION vs UNION ALL
- MySQL - MINUS Operator
- MySQL - INTERSECT Operator
- MySQL - INTERVAL Operator
- MySQL Joins
- MySQL - Using Joins
- MySQL - Inner Join
- MySQL - Left Join
- MySQL - Right Join
- MySQL - Cross Join
- MySQL - Full Join
- MySQL - Self Join
- MySQL - Delete Join
- MySQL - Update Join
- MySQL - Union vs Join
- MySQL Keys
- MySQL - Unique Key
- MySQL - Primary Key
- MySQL - Foreign Key
- MySQL - Composite Key
- MySQL - Alternate Key
- MySQL Triggers
- MySQL - Triggers
- MySQL - Create Trigger
- MySQL - Show Trigger
- MySQL - Drop Trigger
- MySQL - Before Insert Trigger
- MySQL - After Insert Trigger
- MySQL - Before Update Trigger
- MySQL - After Update Trigger
- MySQL - Before Delete Trigger
- MySQL - After Delete Trigger
- MySQL Data Types
- MySQL - Data Types
- MySQL - VARCHAR
- MySQL - BOOLEAN
- MySQL - ENUM
- MySQL - DECIMAL
- MySQL - INT
- MySQL - FLOAT
- MySQL - BIT
- MySQL - TINYINT
- MySQL - BLOB
- MySQL - SET
- MySQL Regular Expressions
- MySQL - Regular Expressions
- MySQL - RLIKE Operator
- MySQL - NOT LIKE Operator
- MySQL - NOT REGEXP Operator
- MySQL - regexp_instr() Function
- MySQL - regexp_like() Function
- MySQL - regexp_replace() Function
- MySQL - regexp_substr() Function
- MySQL Fulltext Search
- MySQL - Fulltext Search
- MySQL - Natural Language Fulltext Search
- MySQL - Boolean Fulltext Search
- MySQL - Query Expansion Fulltext Search
- MySQL - ngram Fulltext Parser
- MySQL Functions & Operators
- MySQL - Date and Time Functions
- MySQL - Arithmetic Operators
- MySQL - Numeric Functions
- MySQL - String Functions
- MySQL - Aggregate Functions
- MySQL Misc Concepts
- MySQL - NULL Values
- MySQL - Transactions
- MySQL - Using Sequences
- MySQL - Handling Duplicates
- MySQL - SQL Injection
- MySQL - SubQuery
- MySQL - Comments
- MySQL - Check Constraints
- MySQL - Storage Engines
- MySQL - Export Table into CSV File
- MySQL - Import CSV File into Database
- MySQL - UUID
- MySQL - Common Table Expressions
- MySQL - On Delete Cascade
- MySQL - Upsert
- MySQL - Horizontal Partitioning
- MySQL - Vertical Partitioning
- MySQL - Cursor
- MySQL - Stored Functions
- MySQL - Signal
- MySQL - Resignal
- MySQL - Character Set
- MySQL - Collation
- MySQL - Wildcards
- MySQL - Alias
- MySQL - ROLLUP
- MySQL - Today Date
- MySQL - Literals
- MySQL - Stored Procedure
- MySQL - Explain
- MySQL - JSON
- MySQL - Standard Deviation
- MySQL - Find Duplicate Records
- MySQL - Delete Duplicate Records
- MySQL - Select Random Records
- MySQL - Show Processlist
- MySQL - Change Column Type
- MySQL - Reset Auto-Increment
- MySQL - Coalesce() Function
MySQL FLUSH Statement
The FLUSH statement in MySQL is used to clear the caches.
Syntax
Following is the syntax of MySQL FLUSH statement −
FLUSH [NO_WRITE_TO_BINLOG | LOCAL] { BINARY LOGS | ENGINE LOGS | ERROR LOGS | GENERAL LOGS | HOSTS | LOGS | PRIVILEGES | OPTIMIZER_COSTS | RELAY LOGS | SLOW LOGS | STATUS | USER_RESOURCES }
Following are various (options) FLUSH statements −
FLUSH BINARY LOGS; FLUSH ENGINE LOGS; FLUSH ERROR LOGS; FLUSH GENERAL LOGS; FLUSH HOSTS; FLUSH LOGS; FLUSH PRIVILEGES; FLUSH OPTIMIZER_COSTS; FLUSH RELAY LOGS; FLUSH STATUS; FLUSH USER_RESOURCES;
The FLUSH TABLES statement
Using the FLUSH tables statement you can flush the data in the table or acquire locks.
Syntax
Following is the syntax of the FLUSH TABLES statement −
FLUSH TABLES { tbl_name [, tbl_name] ... | WITH READ LOCK | tbl_name [, tbl_name] ... WITH READ LOCK | tbl_name [, tbl_name] ... FOR EXPORT }
Example
Suppose we have created a table that contains the sales details along with the contact details of the customers as shown below −
CREATE TABLE SALES_DETAILS ( ID INT, ProductName VARCHAR(255), CustomerName VARCHAR(255), DispatchDate date, DeliveryTime time, Price INT, Location VARCHAR(255), CustomerAge INT, CustomrtPhone BIGINT, DispatchAddress VARCHAR(255), Email VARCHAR(50) );
Now, let’s insert 2 records into the above created table using the INSERT statement as −
Insert into SALES_DETAILS values (1, 'Key-Board', 'Raja', DATE('2019-09-01'), TIME('11:00:00'), 7000, 'Hyderabad', 25, '9000012345', 'Hyderabad – Madhapur', 'pujasharma@gmail.com'); (2, 'Mobile', 'Vanaja', DATE('2019-03-01'), TIME('10:10:52'), 9000, 'Chennai', 30, '9000012365', 'Chennai- TNagar', 'vanajarani@gmail.com');
If we want another table with just the contact details of the customer create a table as −
CREATE TABLE CustContactDetails ( ID INT, Name VARCHAR(255), Age INT, Phone BIGINT, Address VARCHAR(255), Email VARCHAR(50) );
Following query insets records into the CustContactDetails table using the INSERT INTO SELECT statement. Here, we are trying to insert records from the SALES_DETAILS table to CustContactDetails table −
INSERT INTO CustContactDetails (ID, Name, Age, Phone, Address, Email) SELECT ID, CustomerName, CustomerAge, CustomrtPhone, DispatchAddress, Email FROM SALES_DETAILS WHERE ID = 1 AND CustomerName = 'Raja'; INSERT INTO CustContactDetails (ID, Name, Age, Phone, Address, Email) SELECT ID, CustomerName, CustomerAge, CustomrtPhone, DispatchAddress, Email FROM SALES_DETAILS WHERE ID = 2 AND CustomerName = 'Vanaja';
You can verify the contents of the CustContactDetails table as shown below −
SELECT * FROM CustContactDetails;
Output
Following is the output of the above query −
ID | Name | Age | Phone | Address | |
---|---|---|---|---|---|
1 | Raja | 25 | 9000012345 | Hyderabad - Madhapur | pujasharma@gmail.com |
2 | Vanaja | 30 | 9000012365 | Chennai - TNagar | vanajarani@gmail.com |
Following set of queries locks the instance flushes the above created tables and unlocks the instance.
LOCK INSTANCE FOR BACKUP; FLUSH TABLES emp, custcontactdetails WITH READ LOCK; UNLOCK TABLES; UNLOCK INSTANCE;
To Continue Learning Please Login
Login with Google