db2 sql interview questions

SQL server interview questions, SQL SERVER interview questions I went to the interview today and got caught by a small database problem. I am ashamed and brave.

as follows: SELECT * from WHERE >= (SELECT from articles WHERE = 123 ORDER by 10000 1 Ten 3. How does the MySQL index be implemented? What's the problem? Simply understood, the index is to speed up the query . The index is stored independently, so when the amount of data is large, updating the table to update the index at the same time, causing the update speed down . Here I have referred to two articles, the address is as follows: http://fangjian0423.github.io/2017/07/05/mysql-index-summar

One SQL interview question (row and column Interchange), SQL questions There is a high probability that an SQL question will appear during the interview. Recently, some students will still encounter such a question during the

where E1.mgr =E2.empno (+);Find two jobs with the highest average wage, grouped by positionSELECT * FROM (select AVG (SAL) from emp order BY job desc) where rownumselect= "D.dname=" "from=" "emp=" "dept=" "d=" "where=" "and=" "E.sal=" "> (selectMax (SAL) fromEMP where deptno=20) and E.deptno=d.deptnoJob categories with average wage greater than 20002018/5/31 Oracle Database interview Written questions summ

Junior SQL Server developer interview questions Written by: Jeremy kadlec From: Http://www.mssqltips.com/tip.asp? Tip = 1644 ProblemWe are in the process of trying to hireJunior SQL Server developer to work on a few of our projects. WhatExpectations shocould we have on their skill set? What are some fairQuestions to

Jessonlv-lu guodong Original article, reproduced please indicate the source: http://blog.csdn.net/jessonlv The interview questions I encountered during the interview mainly focused on the joint query of SQL. google made a mistake, but I fixed the mistake and shared it with you: Problem description:Create three tables t

Analysis of Java interview questions and prevention of SQL injection, semi QL This article focuses on a common question in the Java interview questions, how to judge and prevent SQL Injection problems. The details are as follows.

Label:A few days ago to participate in an interview, interview company to do a set of questions, SQL problem is not difficult, but I was the first to write the wrong, come back, write the next. Simply record it, 1. Title: 2. Test data SELECT * from student; INSERT into student (Name,subject,score) VALUES (' Zhang

mathematical score of 2-3 (Requirements display field: Student number, name, subject, score)Answer: Select t3.* from (select top 2 t2.* from (select Top 3 name,subject,score,stuid from Stuscore where subject= ' math ' order by score Desc) T2 ORDER by T2.score) T3 ORDER BY T3.score Desc11. Find out the ranking of John Doe's mathematical achievementsAnswer: Declare @tmp table (PM int,name varchar (), score int,stuid int) insert INTO @tmp select Null,name,score,stuid from Stuscore where subject= '

When interviewing the SQL Server database developer, I used a set of standard benchmark technical questions. The following problems are the problems that I think can really help eliminate unqualified candidates. They are arranged in the order of ease to difficulty. When you ask questions about the primary key and foreign key, the following

Tags: sql face question SQL exerciseStructure of the tableStudent (s#,sname,sage,ssex) Student tableCourse (c#,cname,t#) timetableSC (s#,c#,score) score tableTeacher (t#,tname) Teacher table 1. Creating the corresponding table CREATE table student (' s# ' int, sname varchar (+), Sage int, s Sex varchar) The following omit 2. Inserting data insert into student Select 1, ' Zhang San ', 18, ' Male ' union A

formatting results returned by the function are not updatable.3. Functions that return scalar valuesA user-defined function can return a scalar value. Difference between the two 1. In general, the function of the stored procedure implementation is a bit more complex, and the function implementation of the function is relatively strong. 2. Parameters can be returned for stored procedures, and functions can only return values or table objects. 3. The stored procedure is typically performed as a

security.Even so far, some people don't even know the basic semantics of SQL syntax.String sql = "SELECT * from Tb_name where name= '" +varname+ "' and passwd= '" +varpasswd+ "'";If we pass [' or ' 1 ' = ' 1] in as varpasswd. User name feel free to see what will become?SELECT * from tb_name = ' random ' and passwd = ' or ' 1 ' = ' 1 ';Because ' 1 ' = ' 1 ' is sure to be true, so you can pass any validation

Q A location: http://space.cnblogs.com/q/20546/q A: I have asked more questions about the relationship: 5 [resolved issues] Browse: 52 times 00 Student table T1 Stu_id Stu_name 1 Zhang San 2 Li Si 3 Wang Wu Course list T2 Co_id Co_name 1 Java 2 C # 3 C 4 C ++ 5 Javascript Link Table T3 Stu_id Co_id

A few days to a company in Pudong to interview, feel that there is a database query questions did not answer well, self-summary, the next attention.Title: The size of tables in the database, and arranged out. Write the corresponding SQL statement.The code is as follows:CREATE PROCEDURE [dbo].[Gettablespace]@dbNamesysname= "',--database name, default current datab

This post is intended to include some SQL interview questions I have encountered or seen online, which is equivalent to a personal record. It will be updated continuously in the future. 2.3.9 There is such a table Fans (Team, nationality, fancount) 'Barri', 'Germany ', 12000'Barri', 'Spain ', 18000'Barri', 'China', 13000'Barri', 'usa', 15000'Ba

SQL database Interview Questions and answers (22:52:54) ReprintedBytes Summary of course number of three c courses by Ye Ping Category: Program World Student (S #, Sname, Sage, Ssex) Student table S #: Student ID; Sname: Student name; Sage: Student age; Ssex: Student genderCourse (C #, Cname, T #) curriculum C #, Course No.; Cname: Course name; T #: Instructor No

reviews.③ (Recruiting for an insurance project) "I don't have much experience with spring MVC, so there are some unanswered questions, mostly developed using the JSP+SERVLET+JDBC model (this is truth, but if he's prepared before the interview, it shouldn't be said), But I have done insurance-related projects, the customer is XX, to achieve the insurance project in the XX process, and I know some background

general answer. ️ Innodb_buffer_pool_size this parameter is used to buffer data and indexes, and can linearly improve performance. The maximum value can be set to 7% of the memory size. The slow query log is opened and the parameter log-queries-not-using-indexes is added to facilitate the optimization of all SQL statements not indexed in the system. Explain performs query analysis using explain to check whether indexes are used and the number of rows

Summary of Java back-end development interview questions of major companies, and java back-end interview questions ThreadLocal (thread variable copy) Synchronized implements Memory sharing. ThreadLocal maintains a local variable for each thread. It uses space for time, which is used for data isolation between threads