Ques:- How can you generate debugging output from PL/SQL?
Asked In :-
Ospyn Technologies, juris technologies,
Ques:- Which will fire first ? Trigger or Constraint
Asked In :-
CEIPAL SOLUTIONS PVT, Nalsoft, think-cell, autoscout24, jobandtalent, raja software labs, image infosystems,
Ques:- Differentiate between %type and %rowtype attribute in Oracle PL/AQL programming ?
Ques:- What is the Query Optimizer. How you optimize your qeury.
Asked In :-
Young Globes, zyxware technologies,
Right Answer:
The Query Optimizer is a component of a database management system that determines the most efficient way to execute a given SQL query by evaluating different execution plans. To optimize a query, you can:
1. Use proper indexing.
2. Avoid SELECT * and specify only the needed columns.
3. Use WHERE clauses to filter data early.
4. Analyze and rewrite complex joins.
5. Use EXPLAIN to understand the query execution plan.
6. Limit the use of subqueries and consider using JOINs instead.
7. Optimize data types and avoid unnecessary type conversions.
The Query Optimizer is a component of a database management system that determines the most efficient way to execute a given SQL query by evaluating different execution plans. To optimize a query, you can:
1. Use proper indexing.
2. Avoid SELECT * and specify only the needed columns.
3. Use WHERE clauses to filter data early.
4. Analyze and rewrite complex joins.
5. Use EXPLAIN to understand the query execution plan.
6. Limit the use of subqueries and consider using JOINs instead.
7. Optimize data types and avoid unnecessary type conversions.
Ques:- Select * from emp,dept,loc where emp.deptno left outer join dept.deptno and dept.locno=loc.locno.No need to consider the syntax but is it possible to have left outer join and equi join in the same SQL like this ?can we have right outer join and left outer join in the same SQL —
Asked In :-
Code Board Technology, UIDAI, EWALL Solutions, SONATA SOFTWARE LIMITED, corelogic, locuz enterprise solutions ltd, shield ai, crest infotech,
Ques:- I have an employment table whch has salary,dept,name? i want salary b/w 1000 to 5000 can anyone pls say the query for ths ?
Asked In :-
Webtech Developers, Discovery, Inc,
Right Answer:
```sql
SELECT * FROM employment WHERE salary BETWEEN 1000 AND 5000;
```
```sql
SELECT * FROM employment WHERE salary BETWEEN 1000 AND 5000;
```
Ques:- What are the more common pseudo-columns
Asked In :-
Mobily Infotech, Gradeup, Ritwik Software Technologies, getir, coditas, ascent software,
Ques:- In Open SQL statements such as Insert update delete whichone is FASTlLY retrieve the results and which one is Efficient?
Ques:- What is difference between function and procedure?
Right Answer:
A function returns a value and can be used in expressions, while a procedure does not return a value and is used to perform actions.
A function returns a value and can be used in expressions, while a procedure does not return a value and is used to perform actions.
Ques:- Using subquery how can i calculate working days in a month?
Asked In :-
Right Answer:
```sql
SELECT
COUNT(*) AS working_days
FROM
(SELECT
DATE_FORMAT(date_column, '%Y-%m-%d') AS work_date
FROM
your_table
WHERE
MONTH(date_column) = desired_month
AND YEAR(date_column) = desired_year
AND DAYOFWEEK(date_column) NOT IN (1, 7) -- Exclude Sundays (1) and Saturdays (7)
) AS subquery;
```
```sql
SELECT
COUNT(*) AS working_days
FROM
(SELECT
DATE_FORMAT(date_column, '%Y-%m-%d') AS work_date
FROM
your_table
WHERE
MONTH(date_column) = desired_month
AND YEAR(date_column) = desired_year
AND DAYOFWEEK(date_column) NOT IN (1, 7) -- Exclude Sundays (1) and Saturdays (7)
) AS subquery;
```
Ques:- How do you change a password for an existing user via mysqladmin?
Asked In :-
Thryve Digital, palle technologies,
Right Answer:
To change a password for an existing user via `mysqladmin`, use the following command:
```bash
mysqladmin -u username -p'old_password' password 'new_password'
```
Replace `username`, `old_password`, and `new_password` with the appropriate values.
To change a password for an existing user via `mysqladmin`, use the following command:
```bash
mysqladmin -u username -p'old_password' password 'new_password'
```
Replace `username`, `old_password`, and `new_password` with the appropriate values.
Ques:- I want to know last five transactions or records from emp table, from now?
Asked In :-
WhiteSnow Software, calypso technology,
Ques:- Does SQL SERVER Supports “Finally” block?
Asked In :-
CodeClouds IT Solutions,
Right Answer:
No, SQL Server does not support a "finally" block like some other programming languages.
No, SQL Server does not support a "finally" block like some other programming languages.
Ques:- The default type of Constants and variables supported by TSLare..
Asked In :-
Gaian Solutions India, grm,
Right Answer:
The default type of constants and variables supported by TSL (Test Script Language) is "string."
The default type of constants and variables supported by TSL (Test Script Language) is "string."
The MySQL category on takluu.com is tailored for candidates aiming to master the fundamentals and advanced concepts of relational databases. Whether you’re a backend developer, data analyst, DBA, or full-stack engineer, understanding MySQL is essential for working with structured data in real-world applications.
MySQL is one of the most widely used open-source relational database management systems (RDBMS). It is trusted by small startups to large-scale enterprises due to its reliability, scalability, and performance. Interviewers often assess candidates on their ability to write efficient SQL queries, understand relational concepts, normalize data, and manage indexing and performance tuning.
In this section, you’ll find carefully curated interview questions covering a range of topics, including:
-
Basic SQL queries (SELECT, INSERT, UPDATE, DELETE)
-
Joins (INNER, LEFT, RIGHT, FULL)
-
Grouping and aggregate functions (GROUP BY, COUNT, SUM, AVG)
-
Subqueries and nested queries
-
Indexing and performance optimization
-
Transactions, ACID properties, and locks
-
Stored procedures, triggers, and views
-
User management and privileges
This category not only prepares you for syntax-based questions but also for scenario-based problems, such as query optimization, handling large datasets, designing database schemas, and managing concurrency issues.
Our goal is to help you answer MySQL questions with clarity and confidence, demonstrating both your theoretical understanding and practical experience. With real-life examples and mock interview challenges, you’ll be well-prepared to face technical rounds at companies ranging from startups to MNCs.
Use this category as your go-to resource to strengthen your MySQL knowledge, whether you’re preparing for a developer, analyst, or database administrator role.
