What data type is used for phone numbers in sql

In SQL, the data type of phone numbers is generally CHAR or VARCHAR, and the specific choice depends on whether the length of the phone number is fixed. If fixed, use CHAR; if variable, use VARCHAR. In addition, CHAR has better performance and less storage, but it is easy to truncate or fill numbers of different lengths; VARCHAR is flexible and useful for storing extended information, but it wastes space to store short numbers and its performance is not as good as CHAR.

Data type of phone number in SQL

In SQL, the most commonly used data type of phone number isCHARorVARCHAR.

CHAR

• Fixed length character type
• Each character occupies one byte
• For a specific length A phone number (e.g. 10 digits) is perfect

VARCHAR

• Variable length character type
• holds up to Specified maximum length of characters
• More flexible for phone numbers that may vary in length

Choose to use CHAR or VARCHAR

• Use CHAR: When all phone numbers have the same fixed length, such as 10-digit phone numbers.
• Use VARCHAR: When the phone number may vary in length, for example it may contain a country code or extension.

Example

• Fixed length phone number (CHAR)

  CREATE TABLE contacts ( phone_number CHAR(10) );

  Copy after login

• Variable length phone number (VARCHAR)

  CREATE TABLE contacts ( phone_number VARCHAR(20) );

  Copy after login

Advantages

CHAR

• Performs better for fixed-length numbers
• Uses less storage space

VARCHAR

• More flexible for variable-length numbers
• More useful when you need to store additional information such as country codes or extension numbers

Disadvantages

CHAR

• If phone numbers are of different lengths, this may result in data truncation or padding
• Uses more storage space

VARCHAR

• If the length of the phone number is short, it may result in wasted storage space
• Performance may not be as good as CHAR, especially In the case of a large amount of data

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