MySQL Tutorial

MySQL Installation and Configuration

MySQL Database Operations

Database Design

MySQL Data Types

MySQL Storage Engines

MySQL Basic Operations of Tables

MySQL Constraints

MySQL Operators

MySQL Function

MySQL Function Overview

MySQL Manipulate Table Data

MySQL View

MySQL Indexes

MySQL Stored Procedure

MySQL Trigger

MySQL Transactions

MySQL Character Set

MySQL User Management

MySQL Database Backup and Recovery

MySQL Log

MySQL Performance Optimization

MySQL FLOAT, DOUBLE, DECIMAL (decimal type)

MySQL provides several data types for storing decimal and floating point numbers:

FLOAT: The FLOAT data type is used to store single-precision floating point numbers. This means they have around 7 digits of precision. They're stored as 4 bytes.
Example:
```
CREATE TABLE example (
    float_column FLOAT(7, 2)
);
```
The (7,2) means that this number can be up to 7 digits long, with 2 digits after the decimal.
To insert data:
```
INSERT INTO example (float_column) VALUES (12345.67);
```
DOUBLE: The DOUBLE data type is used to store double-precision floating point numbers. This means they have around 15 digits of precision. They're stored as 8 bytes.
Example:
```
CREATE TABLE example (
    double_column DOUBLE(15, 2)
);
```
The (15,2) means that this number can be up to 15 digits long, with 2 digits after the decimal.
To insert data:
```
INSERT INTO example (double_column) VALUES (123456789012345.67);
```
DECIMAL: The DECIMAL data type is used to store exact decimal numbers. Unlike FLOAT and DOUBLE, which can have rounding errors due to the nature of floating-point arithmetic, DECIMAL will store exactly the number you put into it. This makes it ideal for financial and monetary data.
Example:
```
CREATE TABLE example (
    decimal_column DECIMAL(10, 2)
);
```
The (10,2) means that this number can be up to 10 digits long, with 2 digits after the decimal.
To insert data:
```
INSERT INTO example (decimal_column) VALUES (1234567.89);
```

It's worth mentioning that while FLOAT and DOUBLE can store very large or very small numbers (because they're floating point numbers), they're not always exact, and this could lead to rounding errors. On the other hand, DECIMAL is used for exact values where precision is required, such as monetary data.

CREATE TABLE numeric_table (
    id INT PRIMARY KEY,
    float_column FLOAT,
    double_column DOUBLE,
    decimal_column DECIMAL(10, 2)
);

CREATE TABLE float_table (
    id INT PRIMARY KEY,
    float_value FLOAT(8, 4)
);

CREATE TABLE decimal_table (
    id INT PRIMARY KEY,
    decimal_value DECIMAL(10, 5)
);

SELECT 1.1 * 1.1; -- Potential precision loss in FLOAT and DOUBLE
SELECT DECIMAL(1.1, 2) * DECIMAL(1.1, 2); -- Precise arithmetic with DECIMAL

CREATE TABLE double_table (
    id INT PRIMARY KEY,
    double_value DOUBLE(15, 10)
);

CREATE TABLE financial_table (
    id INT PRIMARY KEY,
    amount DECIMAL(10, 2),
    interest_rate FLOAT
);

CREATE TABLE accuracy_table (
    id INT PRIMARY KEY,
    float_val FLOAT,
    double_val DOUBLE
);

CREATE TABLE exact_numeric_table (
    id INT PRIMARY KEY,
    value DECIMAL(8, 4)
);

CREATE TABLE precision_table (
    id INT PRIMARY KEY,
    precise_value DECIMAL(12, 6)
);

CREATE TABLE currency_table (
    id INT PRIMARY KEY,
    total_amount DECIMAL(10, 2),
    exchange_rate DOUBLE
);