answersLogoWhite

0


Best Answer

The CHAR datatype uses a fixed length, where as the VARCHAR datatype can be variable in length up to the maximum value specified for the length.

If you insert "Hello" into a CHAR(10) field, the column would actually contain "Hello " with 5 trailing spaces.

The same value inserted in a VARCHAR(10) field would contain "Hello".

char datatype is fixed length data type and it store maximum 255 characters while varchardatatype store up to 4000 character of variable length datatype

User Avatar

Wiki User

14y ago
This answer is:
User Avatar

Add your answer:

Earn +20 pts
Q: What is the difference between char and varchar data types?
Write your answer...
Submit
Still have questions?
magnify glass
imp
Continue Learning about Basic Math

Difference between an unsigned and a signed type?

The qualifier signed or unsigned may be applied to char or any integer. unsigned numbers are always positive or zero, and obey the laws of arithmetic modulo 2n, where n is the number of bits in the type. So, for instance, if charsare 8 bits, unsigned charvariables have values between 0 and 255, while signed charshave values between -128 and 127 (in a two's complement machine.) Whether plain charsare signed or unsigned is machine-dependent, but printable characters are always positive.


How do you convert decimal number to ASCII code?

That depends on what language you're using. In PHP for example, it would be like this: $c = chr($i); In C, it would be: char c = (char)i; in BASIC, you'd use: LET C$ = CHR$(I)


'c' code to compare two strings using strcmp function?

char one [] = "A string" ;char two [] = "Different String" ;if (strcmp (one, two) == 0){puts ("The two strings are identical") ;}else{puts ("The two strings are different") ;}


Do while loop examples?

i=0; do{ i++; }while(i<10);


What is the first step to use in detecting data type mismatch errors?

Better if you use javascript or another scripting language to analyse what is sent to the server in the first place. Most of the browsers support javascript.Suppose there is an input type of text of the simple html formName:Age : // The button below makes sure that client side validation is done otherwise it doesn't send data to servers // Here the "return checkData()" forces the client-side validation to occur before sending it to serverfunction checkData(){var char = /^[a-zA-Z]+$/;var num= /^[0-9]+$/;var name = document.getElementById("name");var age = document.getElementById("age");if(name.value==""name.value.match(num)){alert("Namespace cannot contain numericals!!");return false;}else if(age.value==""age.value.match(char)){alert("Age cannot be empty or contain characters!!");return false;}else{form1.form.submit();return true;}}// The neat little code tells if javascript is enabled/disabled in browserYour browser doesn't support javascriptMost of things would be easy this way but alas things aren't so easy. You also need to validate data on the server side using echo statements & control loops before finally posting data in mysql table

Related questions

Difference between char and varchar datatypes?

Char is fixed length, while Varchar is variable length.


What is the difference between varchar and char?

Varchar cuts off trailing spaces if given a shorter word than its declared length, while char does not. Char will pad spaces after it if given a shorter word.


What is the difference between char and varchar2 in dbms?

no diff between varchar and varchar2 char store only chacter type but varchar2 store variable chacters. also varchar2 shirinks the space if not fully filled but char cant.


What is var char in php?

Varchar in SQL means string in PHP.


What is the difference between tar and char?

The spelling!


Different between oracle datatypes char20 and varchar20?

In Oracle, the char(20) datatype is a fixed length character string. It will always use 20 characters in the block. If the value contained in the field is less than 20 characters, it will be padded on the right (or the left, depending on coding) with spaces. In Oracle, the varchar(20) datatype is a variable length character string. It will use betwen 1 and 21 characters in the block, 1 for the length, and 0-20 for the data. Its effective length can range between 0 and 20 characters. Note, however, that a string of length 0 is indistinguishable from a null value. This is a deviation from the SQL standard that Oracle acknowledges, but fixing it would break too much existing code. Note also that comparing a char against a varchar is problematic. With the trailiing spaces, the char is not the same as a varchar containing the same characters. Predicates involving these mixed types should use the rtrim expression on the char datatype. (Example: while rtrim(mycharvalue) = myvarcharvalue) Note also that varchar is obsolete. Current code should use varchar2, such as varchar2(20).


What is the difference between statements in c plus plus charconstp and char constp?

There is no difference. Both statements are invalid.


Difference between const char and char const?

const char *p means the char value pointed by 'p' is constant we can't change anyway but the address(location) of 'p' can change. char const *p means the char value pointed by 'p' can change but the location of p can't be change it is constant.


Difference between number and text type field in ms access?

This is true in any database (Access, Oracle). A number field is technically called a "NUMERIC" field. Only numbers can be inserted into a field that has this designator. A text field is for characters or numbers. It can be a "CHAR" (character), a VARCHAR (characters or numbers). It's basically a way of putting rules on columns--what type of data belongs there.


What are different types of char?

signed and unsigned


Difference between char pointer and char buffer?

The difference here is that char *p = "Hello"; will place Hello world in the read-only parts of the memory and making p a pointer to that, making any writing operation on this memory illegal. While doing: char p[] = "Hello"; puts the literal string in read-only memory and copies the string to newly allocated memory on the stack. p[0] = 'A'; is legal.


What are the different between'a' and ''a in java string methods?

The difference between 'a' and "a" anywhere in Java is that 'a' is a primitive char type, while "a" is a String object.