﻿ SQL Challenges-1: Audience in the match - w3resource

# SQL Challenges-1: Execution of orders: Audience in the match

## SQL Challenges-1: Exercise-20 with Solution

From the following table write an SQL query to display the records with four or more rows with consecutive match_no's, and the crowd attended more than or equal to 50000 for each match. Return match_no, match_date and audience. Order the result by visit_date, descending.

Input:

Table: match_crowd

Structure:

FieldTypeNullKeyDefaultExtra
match_noint(11)YES
match_datedateNOPRI
audienceint(11)YES

match_date is the primary key for the match_crowd table.

Data:

match_nomatch_dateaudience
12016-06-1175113
22016-06-1262343
32016-06-1343035
42016-06-1455408
52016-06-1538742
62016-06-1663670
72016-06-1773648
82016-06-1852409
92016-06-1967291
102016-06-2049752
112016-06-2128840
122016-06-2232836
132016-06-2344268

Sample Solution:

SQL Code(MySQL):

``````CREATE TABLE match_crowd (match_no int, match_date date not null unique, audience int);
INSERT INTO match_crowd VALUES ( 1,'2016-06-11',  75113 );
INSERT INTO match_crowd VALUES ( 2,'2016-06-12',  62343 );
INSERT INTO match_crowd VALUES ( 3,'2016-06-13',  43035 );
INSERT INTO match_crowd VALUES ( 4,'2016-06-14',  55408 );
INSERT INTO match_crowd VALUES ( 5,'2016-06-15',  38742 );
INSERT INTO match_crowd VALUES ( 6,'2016-06-16',  63670 );
INSERT INTO match_crowd VALUES ( 7,'2016-06-17',  73648 );
INSERT INTO match_crowd VALUES ( 8,'2016-06-18',  52409 );
INSERT INTO match_crowd VALUES ( 9,'2016-06-19',  67291 );
INSERT INTO match_crowd VALUES (10,'2016-06-20',  49752 );
INSERT INTO match_crowd VALUES (11,'2016-06-21',  28840 );
INSERT INTO match_crowd VALUES (12,'2016-06-22',  32836 );
INSERT INTO match_crowd VALUES (13,'2016-06-23',  44268 );

SELECT DISTINCT m.match_no, m.match_date, m.audience
FROM match_crowd m,
(SELECT m1.match_no AS FROM_ID, m1.match_no+2 AS TO_ID
FROM match_crowd m1, match_crowd m2, match_crowd m3
WHERE m1.match_no+1 = m2.match_no
AND m2.match_no+1 = m3.match_no
AND m1.audience >= 50000
AND m2.audience >= 50000
AND m3.audience >= 50000) m2
WHERE m.match_no BETWEEN m2.FROM_ID AND m2.TO_ID;
```
```

Sample Output:

```match_no|match_date|audience|
--------|----------|--------|
6|2016-06-16|   63670|
7|2016-06-17|   73648|
8|2016-06-18|   52409|
9|2016-06-19|   67291|
```

OR

SQL Code(MySQL):

``````SELECT DISTINCT m1.*
FROM match_crowd m1
JOIN match_crowd m2
JOIN match_crowd m3
ON ((m1.match_no = m2.match_no - 1 AND m1.match_no = m3.match_no -2)
OR (m3.match_no = m1.match_no - 1 AND m3.match_no = m2.match_no -2)
OR (m3.match_no = m2.match_no - 1 AND m3.match_no = m1.match_no -2))
WHERE m1.audience >= 50000
AND m2.audience >= 50000
AND m3.audience >= 50000
ORDER BY m1.match_no;
``````

SQL Code Editor:

﻿

## SQL: Tips of the Day

How to select the nth row in a SQL database table?

Basically, PostgreSQL and MySQL supports the non-standard:

```SELECT...
LIMIT y OFFSET x
```

Oracle, DB2 and MSSQL supports the standard windowing functions:

```SELECT * FROM (
SELECT
ROW_NUMBER() OVER (ORDER BY key ASC) AS rownumber,
columns
FROM tablename
) AS foo
WHERE rownumber <= n
```

Database: SQL

Ref: https://bit.ly/3zPxcD8