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Fix syntax issue

This commit is contained in:
Kamran Ahmed
2025-08-15 21:24:05 +01:00
parent bb47e557c6
commit 4931ba060f
2 changed files with 40 additions and 15 deletions

View File

@@ -2,21 +2,14 @@ Function scope refers to the scope of variables defined within a function. You c
```javascript
function myStudyPlan() {
var studyPlanOne = "Top JavaScript interview questions for web developers";
let studyPlanTwo = "Top JavaScript interview questions for web developers";
const studyPlanThree = "Top JavaScript interview questions for web developers";
var studyPlanOne = "Top JavaScript interview questions for web developers";
let studyPlanTwo = "Top JavaScript interview questions for web developers";
const studyPlanThree = "Top JavaScript interview questions for web developers";
console.log(studyPlanOne);
console.log(studyPlanTwo);
console.log(studyPlanThree);
console.log(studyPlanOne);
console.log(studyPlanTwo);
console.log(studyPlanThree);
}
myStudyPlan(); // Calls the function
myStudyPlan(); // Calls the function
```

View File

@@ -0,0 +1,32 @@
You use **WHERE** for filtering rows before applying any grouping or aggregation.
The code snippet below illustrates the use of **WHERE**. It filters the `Users` table for rows where the `Age` is greater than 18.
```sql
SELECT * FROM Users
WHERE Age > 18;
```
The result of the query is similar to the table below.
| userId | firstName | lastName | age |
| ------ | --------- | -------- | --- |
| 1 | John | Doe | 30 |
| 2 | Jane | Don | 31 |
| 3 | Will | Liam | 25 |
| 4 | Wade | Great | 32 |
| 5 | Peter | Smith | 27 |
On the other hand, you use **HAVING** to filter groups after performing grouping and aggregation. You apply it to the result of aggregate functions, and it is mostly used with the **GROUP BY** clause.
```sql
SELECT FirstName, Age FROM Users
GROUP BY FirstName, Age
HAVING Age > 30;
```
The code above selects the `FirstName` and `Age` columns, then groups by the `FirstName` and `Age`, and finally gets entries with age greater than 30. The result of the query looks like this:
| firstName | age |
| --------- | --- |
| Wade | 32 |
| Jane | 31 |