As the name suggests, varchar means character data that is varying. Also known as Variable Character, it is an indeterminate length string data type. It can hold numbers, letters and special characters. … SQL varchar usually holds 1 byte per character and 2 more bytes for the length information.
What is varchar in SQL with example?
VARCHAR is a variable length string data type, so it holds only the characters you assign to it. VARCHAR takes up 1 byte per character, + 2 bytes to hold length information. For example, if you set a VARCHAR(100) data type = ‘Jen’, then it would take up 3 bytes (for J, E, and N) plus 2 bytes, or 5 bytes in all.
When should I use varchar in SQL Server?
If you use char or varchar, we recommend to:
- Use char when the sizes of the column data entries are consistent.
- Use varchar when the sizes of the column data entries vary considerably.
- Use varchar(max) when the sizes of the column data entries vary considerably, and the string length might exceed 8,000 bytes.
What does varchar 20 mean?
The data type of varchar is Variable-length with non-Unicode character data. The storage size is the actual length of data entered + 2 bytes. • For varchar (20): The max storage size is: 20*1 byte +2 bytes=22 bytes; •
What is difference between varchar and char?
The basic difference between Char and Varchar is that: char stores only fixed-length character string data types whereas varchar stores variable-length string where an upper limit of length is specified.
What is VARCHAR value?
Values in VARCHAR columns are variable-length strings. The length can be specified as a value from 0 to 65,535. The effective maximum length of a VARCHAR is subject to the maximum row size (65,535 bytes, which is shared among all columns) and the character set used. See Section 8.4.
What does VARCHAR 50 mean?
Varchar(50) stores a maximum of 50 characters. Varchar(max) stores a maximum of 2,147,483,647 characters. But, varchar(50) keeps the 50 character space even if you don’t store 50 characters. but varchar(max) is flexible to any size.
Is VARCHAR alphanumeric?
The CHAR and VARCHAR2 datatypes store alphanumeric data. Character data is stored in strings, with byte values corresponding to the character encoding scheme (generally called a character set or code page).
Which is better char or VARCHAR?
CHAR is a fixed length field; VARCHAR is a variable length field. If you are storing strings with a wildly variable length such as names, then use a VARCHAR, if the length is always the same, then use a CHAR because it is slightly more size-efficient, and also slightly faster.
What does VARCHAR 255 mean?
The length can be specified as a value from 0 to 65,535. The effective maximum length of a VARCHAR is subject to the maximum row size (65,535 bytes, which is shared among all columns) and the character set used. … VARCHAR(255) stores 255 characters, which may be more than 255 bytes.
Is varchar 255 bad?
VARchar (255) is generally abad choice unless you need that much space. YOU always wmake all fields the size they need to be and no more. … You don’t want to give room for junk to be put into a field if you can help it. Bad data in means bad data out.
Should I use varchar 255?
255 is used because it’s the largest number of characters that can be counted with an 8-bit number. … When used this way, VarChar only uses the number of bytes + 1 to store your text, so you might as well set it to 255, unless you want a hard limit (like 50) on the number of characters in the field.
What does varchar number mean?
means a varying length character data type, and where n is the number of characters it can store.
What is VarChar2?
The VarChar2 data type is used to store the character values. It is a variable-length data type i.e we can change the size of the character variable at execution time. Hence, it is also called a Dynamic datatype. It is used to store normal characters and alphanumeric characters too.
Why we use VarChar2 instead of VARCHAR?
Varchar stands for variable length character string. Both Varchar and Varchar2 are data types to store character strings for particular column (field) in databases. … If we relay empty string and NULL being the same, then we should use varchar2 instead of varchar. Because it treats both null and empty strings as same.
How long is VARCHAR?
Although VARCHAR supports the maximum size at 65535 characters, the actual maximum value depends on other columns in the table and character set: Maximum row size is 65535 bytes in MySQL that shared among all columns in the table, except TEXT/BLOB columns.