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Add syntax highlighting for queries

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Kamran Ahmed
2023-07-11 03:47:48 +01:00
parent 8692f05f14
commit 80e80e7d9b
1 changed files with 11 additions and 11 deletions
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src/data/roadmaps/sql/content/104-aggregate-queries/index.md
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@@ -7,7 +7,8 @@ SQL aggregate functions are inbuilt functions that are used to perform some calc
**1. COUNT()** **1. COUNT()**
Counts the number of rows. Counts the number of rows.
```
```sql
SELECT COUNT(column_name) SELECT COUNT(column_name)
FROM table_name FROM table_name
WHERE condition; WHERE condition;
@@ -17,7 +18,7 @@ Counts the number of rows.
Returns the sum of a numeric column. Returns the sum of a numeric column.
``` ```sql
SELECT SUM(column_name) SELECT SUM(column_name)
FROM table_name FROM table_name
WHERE condition; WHERE condition;
@@ -26,7 +27,8 @@ Returns the sum of a numeric column.
**3. AVG()** **3. AVG()**
Returns the average value of a numeric column. Returns the average value of a numeric column.
```
```sql
SELECT AVG(column_name) SELECT AVG(column_name)
FROM table_name FROM table_name
WHERE condition; WHERE condition;
@@ -35,7 +37,8 @@ Returns the average value of a numeric column.
**4. MIN()** **4. MIN()**
Returns the smallest value of the selected column. Returns the smallest value of the selected column.
```
```sql
SELECT MIN(column_name) SELECT MIN(column_name)
FROM table_name FROM table_name
WHERE condition; WHERE condition;
@@ -44,7 +47,8 @@ Returns the smallest value of the selected column.
**5. MAX()** **5. MAX()**
Returns the largest value of the selected column. Returns the largest value of the selected column.
```
```sql
SELECT MAX(column_name) SELECT MAX(column_name)
FROM table_name FROM table_name
WHERE condition; WHERE condition;
@@ -56,7 +60,7 @@ These functions ignore NULL values.
To separate the results into groups of accumulated data, you can use the GROUP BY clause. To separate the results into groups of accumulated data, you can use the GROUP BY clause.
``` ```sql
SELECT column1, aggregate_function(column2) SELECT column1, aggregate_function(column2)
FROM table FROM table
GROUP BY column1; GROUP BY column1;
@@ -73,8 +77,4 @@ GROUP BY column1
HAVING conditions; HAVING conditions;
``` ```
## Conclusion Aggregate queries are simply a way of summarizing information in your database. Although they are a powerful tool, they can become complex very quickly, especially if you start nesting them together or combining multiple aggregate functions in a single query.
Aggregate queries are simply a way of summarizing information in your database. Although they are a powerful tool, they can become complex very quickly, especially if you start nesting them together or combining multiple aggregate functions in a single query.
> Note: The real power of aggregate functions comes when you combine them with the WHERE or HAVING clause, allowing you to filter the data that you are summarizing.