﻿ SQL Challenges-1: Most experienced manager to execute the schemes - w3resource

# SQL Challenges-1: Most experienced manager to execute the schemes

## SQL Challenges-1: Exercise-34 with Solution

From the following tables write a SQL query to find those experienced manager who execute the schemes. Return scheme code and scheme manager ID.

Input:

Table: managing_body

Structure:

FieldTypeNullKeyDefaultExtra
manager_idint(11)NOPRI
manager_namevarchar(255)YES
running_yearsint(11)YES

Data:

manager_idmanager_namerunning_years
51James5
52Cork3
53Paul4
55Hense4
56Peter2

Table: scheme

Structure:

FieldTypeNullKeyDefaultExtra
scheme_codeint(11)NOPRI
scheme_manager_idint(11)NOPRI

Data:

scheme_codescheme_manager_id
100151
100153
100154
100156
100251
100255
100351
100452

Sample Solution:

SQL Code(MySQL):

CREATE TABLE managing_body (manager_id int NOT NULL UNIQUE, manager_name varchar(255), running_years int);

INSERT INTO managing_body VALUES(51,'James',5);
INSERT INTO managing_body VALUES(52,'Cork',3);
INSERT INTO managing_body VALUES(53,'Paul',4);
INSERT INTO managing_body VALUES(55,'Hense',4);
INSERT INTO managing_body VALUES(56,'Peter',2);

CREATE TABLE scheme (scheme_code int NOT NULL , scheme_manager_id int NOT NULL,
PRIMARY KEY(scheme_code,scheme_manager_id));
INSERT INTO scheme VALUES(1001,	51);
INSERT INTO scheme VALUES(1001,	53);
INSERT INTO scheme VALUES(1001,	54);
INSERT INTO scheme VALUES(1001,	56);
INSERT INTO scheme VALUES(1002,	51);
INSERT INTO scheme VALUES(1002,	55);
INSERT INTO scheme VALUES(1003,	51);
INSERT INTO scheme VALUES(1004,	52);

SELECT scheme_code, p.scheme_manager_id
FROM scheme p JOIN managing_body e
ON p.scheme_manager_id = e.manager_id
WHERE (scheme_code, e.running_years) IN
(SELECT scheme_code, MAX(running_years)
FROM scheme p JOIN managing_body e
ON p.scheme_manager_id = e.manager_id
GROUP BY scheme_code);

Sample Output:

scheme_code|scheme_manager_id|
-----------|-----------------|
1001|               51|
1002|               51|
1003|               51|
1004|               52|

SQL Code Editor: