Q41. What does UPPER do?
Converts to uppercase. `LOWER` to lowercase. `INITCAP` (Oracle/PostgreSQL) capitalizes first letter of each word. ```sql SELECT UPPER('hello'); -- HELLO ```
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Q42. Current date in MySQL without time?
In MySQL, you retrieve the current date (year, month, day) without the time component using **`CURDATE()`** or **`CURRENT_DATE`**: ```sql SELECT CURDATE(); -- Example: '2...
Q43. Top 3 students by mark?
```sql -- MySQL / PostgreSQL SELECT name, mark FROM Students ORDER BY mark DESC LIMIT 3; -- SQL Server SELECT TOP 3 name, mark FROM Students ORDER BY mark DESC; -- Oracle...
Q44. Which set operator for "searched but didn't buy"?
`MINUS` (Oracle) or `EXCEPT` (PostgreSQL/SQL Server): ```sql SELECT name FROM searchers WHERE product = 'X' EXCEPT SELECT name FROM buyers WHERE product = 'X'; ``` ---
Q45. What is AUTO_INCREMENT?
Automatically generates sequential unique integers for a column, typically the PRIMARY KEY. ```sql CREATE TABLE users (id INT AUTO_INCREMENT PRIMARY KEY, name VARCHAR(50)...
Q46. Rename column Address to Addr in Customer?
```sql -- MySQL ALTER TABLE Customer CHANGE Address Addr VARCHAR(50); -- PostgreSQL / Standard ALTER TABLE Customer RENAME COLUMN Address TO Addr; ```
Q47. How to use composition API in Vue2.0?
Vue 2.0 does not have native support for the Composition API, but you can use it via the official plugin: `@vue/composition-api`. Let's see the usage in step-by-step inst...
Q48. What is composition API?
The **Composition API** in Vue 3 is a new way to organize and reuse logic in Vue components. It was introduced to address some limitations of the **Options API** (used in...
Q49. What are the benefits of composition API?
The composition API provides several benefits over the traditional Options API as listed below. 1. Better logic reuse and code organization: 2. Better typescript support:...
Q50. What are composition functions?
**Composition functions** (commonly called **Vue Composables**) are functions that leverage Vue's Composition API to encapsulate, manage, and reuse **stateful logic** acr...