Banku (Shanghai) Business Consulting Co., Ltd.

A table named Student contains the following fields: id, classid, name, birth, remark

1. Insert a record: classid = 2 name = Zhang San birth = 1982-07-19;

Answer: insert into student (classid, name, birth) values (2, 'zhang san', '2017-07-19 ')

 

2. Select all students whose classid is 4;

Answer: select * from student where classid = 4

 

3. query all persons with the Year of birth greater than 1976;

Answer: select * from student where birth> '123'

 

4. query the number of people who have been born in each class for more than 1976 years;

Answer: select classid, count (*) as number from student where birth> '123' group by classid

 

5. query the number of students in all classes;

Answer: select classid, count (*) as total from student group by classid

 

6. query all records containing "Plans" in the REMAK;

Answer: select * from student where remark like '% scheduler %'

 

7. Improve SQL efficiency;

Answer: In ASP,

• Use JOIN to write complex SQL statements instead of a bunch of SQL statements: Query all data at a time;
• Use the UPDATE statement instead of rs. update ();
• Batch Processing of SQL statements is more efficient than executing one sentence;
• The where clause first considers the index;
• Avoid using large fields such as TEXT: Large execution efficiency is also high in the database;

Other aspects:

• Replacing temporary tables with embedded views: temporary tables consume a lot of memory and perform a lot of I/O operations;
• Avoid using left join and NULL values, Use inner join, and set the field cannot be NULL;
• Use indexes;
• Use the partition view;
• Use the trigger to run the stored procedure to another statistical table;

 

8. The code is used to print the triangle;

Answer:

 

Code
Private void PascalTriangle (int number)
{
Int I, j, n, m;
N = number;
Int [,] a = new int [20, 20];

For (I = 0; I <n; I ++)
{
A [I, 0] = 1;
A [I, I] = 1;
}

For (I = 2; I <n; I ++)
{
For (j = 1; j <I; j ++)
{
A [I, j] = a [I-1, j-1] + a [I-1, j];
}
}

For (I = 0; I <n; I ++)
{
For (m = 1; m <n-I; m ++)
{
Response. Write ("& nbsp ;");
}

For (j = 0; j <= I; j ++)
{
Response. Write (a [I, j]. ToString ());
Response. Write ("& nbsp ;");
}

Response. Write ("<br> ");
}
}