Which of the following is not a valid SQL type

A) FLOAT

B) NUMERIC

C) DECIMAL

D) CHARACTER

The correct answer to this question “Which of the following is not a valid SQL type “ is option(D)

CHARACTER

Explanation: “CHARACTER” is not a standard SQL type by itself. The correct SQL type for strings would be CHAR or VARCHAR for variable-length strings.

Table of Contents:

• Different Valid SQL Types
  • FLOAT in SQL
  • NUMERIC in SQL
  • DECIMAL in SQL
  • CHAR in SQL
• Conclusion

Different Valid SQL Types

Let’s have a look at valid SQL types:

1. FLOAT in SQL

The FLOAT type is used to store floating-point numbers, which are numbers that can have a fractional part (decimal). FLOAT can hold decimal numbers and is useful for cases where exact accuracy is not a requirement. It is generally used for storing large numbers or when the exact value is less important.

Example :

CREATE TABLE product_prices (
    product_name VARCHAR(50),
    price FLOAT
);

In this example, we create a table named “product_prices”, where the price column uses the FLOAT data type to store the prices of products. This allows for decimal values but with approximate accuracy.

2. NUMERIC in SQL

The NUMERIC type is used for exact numeric values with a specified accuracy and scale. It’s commonly used for financial data, values, and other applications where accuracy is crucial. NUMERIC allows you to define both the total number of digits and the number of digits after the decimal point. It avoids rounding errors by providing exact accuracy.

Example :

INSERT INTO bank_accounts (account_holder, balance)

VALUES ('Alice', 1000.50),

       ('Bob', 2500.75),

       ('Charlie', 1500.25);

In this example, we create a “bank_accounts” table. The balance column uses the NUMERIC(15, 2) data type. In simple words, the NUMERIC(15, 2) data type is used to store numbers that need to be very accurate, like money. The number 15 means that the total number of digits can be up to 15. The number 2 means that there can be up to 2 digits after the decimal point.

3. DECIMAL in SQL

The DECIMAL type is similar to NUMERIC and is used for storing fixed-point numbers with exact accuracy. Both DECIMAL and NUMERIC are used for storing numbers with a specific number of digits before and after the decimal. DECIMAL offers exact accuracy, meaning that rounding errors will not occur during arithmetic operations.

Example :

CREATE TABLE orders (

    order_id INT,

    total_amount DECIMAL(10, 2)  -- 10 digits total, 2 digits after the decimal point

);

In this example, the “total_amount” columns use the DECIMAL(10, 2) data type, which can store the numbers with up to 10 digits in total and 2 digits after the decimal point.

4. CHAR in SQL

CHAR is used to store fixed-length character strings. It is used for strings where the length of the text is always the same.

Example :

CREATE TABLE example (

    code CHAR(5) 

);

This SQL statement creates a table named example with a column called “code” that stores fixed-length strings of exactly 5 characters.

Conclusion

CHARACTER is not a standard SQL type, but data types like FLOAT, NUMERIC, DECIMAL, and CHAR are used to handle different kinds of data with accuracy and efficiency. Each data type is designed for specific use cases, ensuring accurate storage and calculations. Except CHARACTER remaining all options are valid SQL types.