Answer / dinesh goyal

char is used for fixed length memory storage whereas varchar
is used for variable lenght memory storage.
Fox Example if we have char(10) then we can store 10 bit
value in it but if we store only 6 bit value in it then rest
of the 4 bit space is goes wasted. this limitation is
overcome by varchar.
In varchar if we use less space than define space the rest
of space is not wasted.

Answer / preeti singh

The char is a fixed-length character data type, the varchar
is a variable-length character data type.

Because char is a fixed-length data type, the storage size
of the char value is equal to the maximum size for this
column. Because varchar is a variable-length data type, the
storage size of the varchar value is the actual length of
the data entered, not the maximum size for this column.

You can use char when the data entries in a column are
expected to be the same size.
You can use varchar when the data entries in a column are
expected to vary considerably in size.

Answer / paras nath

The char is a fixed-length character data type, the varchar is a variable-length character data type.

Because char is a fixed-length data type, the storage size of the char value is equal to the maximum size for this column. Because varchar is a variable-length data type, the storage size of the varchar value is the actual length of the data entered, not the maximum size for this column.

You can use char when the data entries in a column are expected to be the same size.
You can use varchar when the data entries in a column are expected to vary considerably in size.

Answer / sonu kumar

i m totally aggred with answer no 1 so my answer will be also like that

Answer / deven verma

char stores only character values whereas varchar can
stores alphanumerics values. searching is faster in char in
comparision of varchar

Answer / kav

no

Use mysqldump to create a copy of the database?

2 Answers  

Which statement is used to delete a table in MySQL.

0 Answers  

What is maximum table size in mysql?

0 Answers  

mysql> select * from store; +------+-------+-------+ | id | month | sales | +------+-------+-------+ | 1 | 1 | 100 | | 1 | 2 | 100 | | 1 | 3 | 200 | | 1 | 4 | 300 | | 1 | 5 | NULL | | 1 | 6 | 200 | | 1 | 7 | 800 | | 1 | 8 | 100 | | 1 | 9 | 240 | | 1 | 10 | 140 | | 1 | 11 | 400 | | 1 | 12 | 300 | | 2 | 1 | 300 | | 2 | 2 | 300 | | 2 | 3 | 300 | | 2 | 4 | 200 | | 2 | 5 | 200 | | 2 | 6 | 200 | | 2 | 7 | 100 | | 2 | 8 | 100 | | 2 | 9 | 300 | | 2 | 10 | 100 | | 2 | 11 | 150 | | 2 | 12 | 150 | +------+-------+-------+ this is my table. i need to display output like this. +------+----------+----------+----------+----------+ | id | quarter1 | quarter2 | quarter3 | quarter4 | +------+----------+----------+----------+----------+ | 1 | 400 | 500 | 1140 | 840 | | 2 | 900 | 600 | 500 | 400 | +------+----------+----------+----------+----------+ what single query i have to write for this. i tried this query and it displays like the below mysql> select id,sum(sales) as quarter1,(select sum(sales) from store where mont h>3 and month<7 ) as quarter2,(select sum(sales) from store where month>6 and mo nth<10)as quarter3 from store where month>0 and month<4 group by id; +------+----------+----------+----------+ | id | quarter1 | quarter2 | quarter3 | +------+----------+----------+----------+ | 1 | 400 | 1100 | 1640 | | 2 | 900 | 1100 | 1640 | +------+----------+----------+----------+ 2 rows in set (0.00 sec) tel me how to rectify it.

2 Answers  

How do I change a procedure in mysql?

0 Answers  

Explain the different types of constraints?

0 Answers  

What are string data types?

0 Answers  

How to create trigger in mysql workbench?

0 Answers  

How do I find the size of a mysql database?

0 Answers  

What are the purposes of using enum and set data types?

0 Answers  

What are the advantages of myisam over innodb?

0 Answers  

Where is mysql installed on linux?

0 Answers