On the other side, the NVL2 function check if exp1 is null, if it is indeed null, it will return exp2, otherwise, it will return exp3. Conceptually, it is like the ternary operator for SQL queries.select nvl(null, 'arg2') from dual; //Returns arg2 select nvl('arg1', 'arg2')...
Because of this, so-called soft skills can actually be more important than the actual technological know-how. We can teach someone a lot about Oracle APEX and SQL queries but it’s quite possible that we won’t be able to make them more open, talkative, and charismatic, which is why id...
With bind variables in SQL, Oracle can cache related queries a single time in the SQL cache (area). This avoids a hard parse each time, which saves on various locking and latching resources we use to check objects existence and so on. BONUS: For rarely run queries, especially BATCH querie...
From the software perspective, Oracle is more powerful owing to its extra features. Also, it offers better indexing due to which it provides a competitive benefit over MySQL. 15. What is CHAR and VARCHAR in MySQL?This is one of the most important interview questions on MySQL. Both...
RDBMS software executes the queries on the data like adding and updating the data. The application which comes under the RDBMS category is MySQL, Oracle, Informix, IBM DB2 and Microsoft SQL Server. RDBMS Interview Questions we are mentioning below will help you to gain enough knowledge about ...
Example of Sql Server 2014 SQL format:Example of Oracle SQL format below:Create database:Output: Here we can see our database is created.What is PL/SQL?PL/SQL Control Statements in Oracle.Control Statements,• Control statements are very important in PL/SQL....
This ensures data integrity and supports complex queries. Transactions: They support ACID (Atomicity, Consistency, Isolation, Durability) properties, making them ideal for applications requiring reliable transactions, such as financial systems. Examples: MySQL, PostgreSQL, Oracle Database. NoSQL (Not ...
Linux Internals & Advanced (Scenario based questions): Explain the linux boot process (detailed) BIOS/UEFI: When you power on the computer, the Basic Input/Output System (BIOS) or Unified Extensible Firmware Interface (UEFI) firmware is invoked. It performs hardware initialization, self-tests, ...
When a single heartbeat message from non-master node is not delivered on time, the non-master questions the availability of the master and starts master re-election (in case of gateway node) or searches for a new master (worker node). However, it continues to run the services running on...
This is among the crucial interview questions on MySQL that is a bit technical, but you must know the correct answer. 27. What is a Stored Procedure in MySQL? A stored procedure in MySQL is a group of SQL statements saved in the database. SQL queries such as INSERT, UPDATE, DELETE, ...