Scenario-Based SQL Interview Questions The Bottom Line Top SQL Interview Questions List for 2025 SQL is a common language for Structured Query Language, which is based on general English, whereas MySQL is a data
This scenario can be better implemented by logging all the necessary data into a separate table, and have a job which periodically checks this table and does the needful. 24. What is a self join? Explain it with an example Self join is just like any other join, except that two instances...
For example, the query below updates the salary of employees in department 10 by increasing it by 10%, and then checks whether any rows were affected by theUPDATEstatement using the%NOTFOUNDattribute. If no rows were updated, it outputs a message saying, "No rows were updated." If rows w...
Real Life Scenario: Kindly consider following table.We need to find aggregate results departmentwise in form of rows. Employee table: Employee_numEmployee_nameDepartment IDSalary 1Amit100680000 2Rohan100550000 3Rohit101430000 Query used: select Department_ID,listagg(Employee_name,’,’) within group(...
Also a common job interview question perhaps? I am using the AdventureWorksDW2012 database. Tests were done with SQL Server 2012 SP2 I run each query twice. Once with the base table and once with a covering Index. Here is the covering Index: 1 2 3 CREATE NONCLUSTERED INDEX _E_Dim...
at nearly every scale of operation. The advice in this guide will help you navigate the major milestones of the hiring process, including crafting an attractive and relevant job description and conducting an effective technical interview. Ultimately, the right SQL developer can be instrumental to you...
Scenario He has an application that can only accept 3 data types (NVARCHAR, NUMERIC, and DATETIME), and as all normal database schemas do, his database has more than 3 data types. He needed to identify which column had data types that could not be used and determine which of the 3 da...
ALTER DATABASE [QueryStoreDB] SET QUERY_STORE = ON ( OPERATION_MODE = READ_WRITE, CLEANUP_POLICY = ( STALE_QUERY_THRESHOLD_DAYS = 90 ), DATA_FLUSH_INTERVAL_SECONDS = 900, MAX_STORAGE_SIZE_MB = 1000, INTERVAL_LENGTH_MINUTES = 60, SIZE_BASED_CLEANUP_MODE = AUTO, QUERY_...
SQL-based technologies have a lot in common, and all SQL developers need certain skills to succeed. However, there are many aspects specific to a given SQL engine (like PostgreSQL or MySQL), role (administrator or architect), or optimization scenario (data marts, data lakes, or data warehouse...
We’ll be using VMs for this scenario, and we could use SSMS on the host, but to keep things simple, we’ll be using SSMS on the SQL instance. However, you shouldneverdo this in the real world. Why? The first reason is that Always Encrypted is designed to allow for role separation...