Answer:
The Update statement in the DML is used for changing existing data in a table.
Explanation:
Their are following Sql statement in the DML.
Insert
This SQL statement is used for inserting data into the table.
select
This SQL statement is used for retrieving data from database
update
This SQL statement is used for updating data in a table.
delete
This SQL statement is used for delete data from database .
The "UPDATE" SQL statement in DML is used for Modify the data in the existing table .
Following are the syntax of Update SQL query
Update tablename
set column1=value1,column2=value2............column N=valueN
Where condition;
Example :Suppose we have student table and (rollno,name,age and add) are the field for that table we have to change the address of rollno 105
Then we use update query like that
UPDATE STUDENT
SET add='kalam nagar'
where rollno=105;
Answer and Explanation:
Given that total number of records in a file = 100000
Each record consists of= 240 bytes
Given that B= 2400 bytes.
Then total blocks in file = 100000 records * 240 / 2400
= 10000 blocks.
Time that will take for exhaustive read
= s + r + b.btt
= 16 + 8.3 + (10000) * 0.8
= 8024.3 msec
Now as per given X be the number of records that are searched randomly and it takes more than exhaustive read time.
Hence, X (s + r + btt) > 8024.3
X (16+8.3+0.8) > 8024.3
X > 8024.3/25.1
So that, X > 319.69
Hence, atleast 320 random reads should be made to search the file
Answer:
All of the above
Explanation:
A local variable is a variable which is declared within a method or is an argument passed to a method, it scope is usually local (i.e. it is hidden from other method). it can also have the same name as a local variable in another method and it loses the values stored in them between calls to the method in which the variable is declared. So all the option listed above are correct.
Answer:
The answer is "option d".
Explanation:
UML stands for Unified Modeling Language. It is an OOPs based language that is used to design a graphic by software developers. This language can also be used to build diagrams and provide some tools to ready-to-use, interactive templates for users and other options are not correct that can be described as:
- In option a, The Top-down approach is not followed by UML.
- In option b, UML uses an object-oriented programming language that follows a bottom-up approach. It refers to a style of programming.
- In option c, It does not use structured programming because it uses procedural languages.