Quick Answer: What Is Varchar Data Type?

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; •.

Why varchar is used in SQL?

Also known as Variable Character, it is an indeterminate length string data type. … SQL varchar usually holds 1 byte per character and 2 more bytes for the length information. It is recommended to use varchar as the data type when columns have variable length and the actual data is way less than the given capacity.

Why is 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.

Where is Char and varchar used?

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.

Which is better varchar or text in MySQL?

Some Differences Between VARCHAR and TEXT TEXT fields have a fixed max size of 65,535 characters. … VARCHAR is stored inline with the table (at least for the MyISAM storage engine), making it potentially faster when the size is reasonable. Of course, how much faster depends on both your data and your hardware.

What is a 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.

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.

What does varchar 10 mean?

The reason you use a varchar is exactly why it’s named varchar . It allows you to store variable-sized data elements. Typically, char(10) gives you ten characters, no matter what, padding it with spaces if you insert something shorter.

Should I use char or varchar?

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.

Why char is faster than varchar?

CHAR is also better than VARCHAR for data that’s changed frequently, because a fixed-length row is not prone to fragmentation. … The Memory storage engine uses fixed-size rows, so it has to allocate the maximum possible space for each value even when it’s a variable-length field.

Does varchar reserve space?

Even though the column is variable and the storage space used is variable, MySQL will allocate memory in fixed-chunks to store values. For example varchar(200) will use more memory that varchar(5). This is not a storage space issue, but still something to consider when defining your columns.

What is char and varchar data type?

CHAR datatype is used to store character string of fixed length. VARCHAR datatype is used to store character string of variable length. 2. In CHAR, If the length of string is less than set or fixed length then it is padded with extra memory space.

Is it bad to use varchar Max?

Varchar(max) should only ever be used if the size of the field is known to be over 8K. In every other instance, the size must be specified. Failure to do so is poor design and will lead to performance issues on any but the most trivial of systems.

How is varchar stored?

All varchar data is stored at the end of the row in a variable length section (or in offrow pages if it can’t fit in row). The amount of space it consumes in that section (and whether or not it ends up off row) is entirely dependant upon the length of the actual data not the column declaration.

What is varchar 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.