Dynamic SQL enables the construction ofSQL queries at runtime, allowing flexibility in query execution. It is commonly used forsearch filters, report generation, and metadata-driven applications. Implementation Methods: Using EXECUTE: DECLARE @sqlQuery NVARCHAR(MAX) = 'SELECT * FROM Employees WHERE D...
A query, in SQL, is a command used to request data or update information from a database table or combination of tables. Users can write and execute queries to retrieve, delete or update information in a database. Usually, a query response returns data from different tables within the data...
means. The SQL queries which are used the advanced functionalities to add business logic in the program or to retrieve the specific business related data are called as advanced SQL queries.You can able to learn thecomplex SQL queries,Complex SQL interview questionsand many more things in the ...
As such, we've defined it with a simple foreign key in the orders table pointing to a given customer_id, and we can use JOIN clauses in our SELECT queries fairly easily. Many-to-many relationships are a bit more complicated. For example, what if we had an orders table and a ...
SQL Interview Question #2 You work for a startup that makes an online presentation software. You have an event log that records every time a user inserted an image into a presentation. (One user can insert multiple images.) The event_log SQL table looks like this: user_id event_date_tim...
We can check the current settings and thread allocation using the below queries. –Thread setting select max_workers_count from sys.dm_os_sys_info –Active threads select count(*) from sys.dm_os_threads Default value is 255. Increasing the number of worker threads may actually decrease the ...
This supports faster execution instead of executing multiple queries. This reduces network traffic and provides better security to the data. Disadvantage is that it can be executed only in the Database and utilizes more memory in the database server....
BEGIN: The executable section where SQL queries and procedural statements are written. EXCEPTION(Optional): Handles runtime errors and exceptions to ensure graceful error recovery. END;: Marks the end of the block. 3. What are the essential PL/SQL data types?
Joins are used in queries to explain how different tables are related. Joins also let you select data from a table depending upon data from another table. Types of joins: INNER JOINs, OUTER JOINs, CROSS JOINs.OUTER JOINs are further classified as LEFT OUTER JOINS, RIGHT OUTER JOINS and FULL...
6. How to capture the long running queries? 7. What is the migration plan to move 300 databases to a new data centre? We can have an hour downtime. 8. In mirroring a connection failure happened between principal and mirror and principal server started filling log space (send queue), how...