Wrote all the example queries chapter-wise

README.md

@@ -1,15 +1,380 @@
-# Getting Started with SQL
+# Queries for all the examples chapter-wise
 
-Thank you for reading *Getting Started with SQL*. These are the database files for the book. 
+# Chapter 4 **SELECT** 
 
-# Having Download Trouble?
+### Retrieving Data
+```
+select * FROM PRODUCT;
+```
 
-This book requires basic proficiency in downloading, unzipping, and navigating files and folders. 
+### Expressions in SELECT statements
+```
+select *,PRICE*1.07 FROM PRODUCT;
+select *,PRICE*1.07 AS TAXED_PRICE FROM PRODUCT;
+select *,round(PRICE*1.07,0) AS TAXED_PRICE FROM PRODUCT;
+```
 
-If you need assistance in extracting a zipped folder, [please see this short tutorial](http://www.wikihow.com/Open-a-Zip-File).
+### Describe Table
+```
+pragma table_info('customer');
+```
 
-For SQLiteStudio, easy-to-use installers are now available so you should not have to unzip/copy/paste SQLiteStudio: https://sqlitestudio.pl/index.rvt?act=download
+### Text Concatenation
+```
+select name, city||' '||state as location from customer;
+select name, region|| ' ' || street_address || ',' || city || ',' || state || ',' || zip as shipping_address from customer;
+```
 
+# Chapter 5 **WHERE** 
+### Using Where on Numbers
+```
+select * from station_data where year>2005 and year<2010 ;
+select * from station_data where year between 2005 and 2010;
+```
+### AND, OR and IN statements
+```
+select * from station_data where month=3 or month=6 or month=9 or month=12;
+select * from station_data where month in (3,6,9,12);
+select * from station_data where month not in (3,6,9,12);
+select * from station_data where month%3=0;
+```
 
-![](https://images-na.ssl-images-amazon.com/images/I/51A7fbsp0EL.jpg)
+### Using WHERE on Text
+```
+select * from station_data where length(report_code)=6;
+select * from station_data where report_code like 'b%';
+select * from station_data where report_code like 'b_c%';
+```
 
+### Using WHERE on Booleans
+```
+select * from station_data where tornado=1 and hail=1;
+select * from station_data where tornado and hail;
+select * from station_data where tornado=0 and hail;
+select * from station_data where not tornado and hail;
+```
+### Handling NULL
+```
+select * from station_data where snow_depth is NULL;
+
+//coalesce() function
+select report_code, coalesce(precipitation,0) as rainfall from station_data where precipitation <=0.5;
+select * from station_data where (rain=1 and temperature<=32) or snow_depth>0;
+```
+# Chapter 6 **GROUP BY and ORDER BY**
+### Grouping Records
+```
+select count(*) from station_data where tornado;
+select year, month, count(*) as count from station_data group by year;
+
+// Grouping using ordinal positions
+select count(*) from station_data where tornado;
+select year, month, count(*) as count from station_data group by 1;
+```
+### Ordering Records
+```
+select * from station_data where tornado=1 group by 1,2 order by 1,4 desc;
+```
+### Aggregate Functions
+```
+//sum() function
+select year, sum(snow_depth) from station_data where year>=2000 group by year;
+
+//max() function
+select year, sum(snow_depth) as total_snow , sum(precipitation) as total_precipitation, max(precipitation) from station_data where year>=2000 and tornado group by year;
+```
+### HAVING Statement
+```
+select year, sum(precipitation) from station_data  group by year having precipitation>0.5;
+```
+### Getting DISTINCT Records
+```
+select DISTINCT STATION_NUMBER FROM STATION_DATA ORDER BY STATION_NUMBER ASC;
+```
+
+# Chapter 7 **CASE Statements**
+
+### The CASE Statement
+```
+select report_code,year,month,wind_speed, 
+    CASE 
+        when wind_speed>=4 then 'high' 
+        when wind_speed between 3 and 4 then 'moderate' 
+        else 'low' end as wind_severity 
+from station_data;
+
+//More efficient method
+select report_code,year,month,wind_speed, 
+CASE 
+    when wind_speed>=4 then 'high' 
+    when wind_speed >=3 then 'moderate' 
+    else 'low' 
+END AS wind_severity 
+from station_data;
+```
+
+### Grouping CASE Statements
+```
+select year, 
+CASE 
+    when wind_speed>=4 then 'high' 
+    when wind_speed >=3 then 'moderate' 
+    else 'low' 
+END AS wind_severity ,
+count(*) as count
+from station_data 
+GROUP BY 1,2;
+```
+
+### The "Zero/Null" CASE Trick
+```
+select year, month,
+sum(case 
+    when tornado=0 then precipitation
+    else 0 END)
+AS non_tornado_precipitation,
+sum(case 
+    when tornado=1 then precipitation
+    else 0 END)
+as tornado_precipitation
+from station_data
+group by year,month;
+```
+```
+select year,month,
+max(case when tornado=1 then precipitation else Null end) as max_precipitation_tornado,
+max (case when tornado=0 then precipitation else NULL end) as max_precipitation_non_tornado
+from station_data
+group by year;
+```
+```
+select month,
+avg(case when rain or hail then temperature else NULL end) as avg_preicpitation_temp,
+avg(case when not (rain or hail) then temperature else NULL end) as avg_non_precipitation_temp
+from station_data
+where year>2000
+group by month
+```
+
+# Chapter 8 **JOIN**
+## INNER JOIN
+```
+select order_id, customer.customer_id, order_date, ship_date, name, street_address, street_Address, city, state, zip,product_id, order_qty
+from customer inner join customer_order 
+on customer.CUSTOMER_ID= customer_order.CUSTOMER_ID;
+```
+## LEFT JOIN
+```
+select order_id, customer_id, order_date, 
+ship_date, name, street_address, street_Address, 
+city, state, zip,product_id, order_qty
+from customer LEFT join customer_order 
+on customer.CUSTOMER_ID= customer_order.CUSTOMER_ID;
+```
+```
+SELECT ORDER_ID, CUSTOMER_ID,NAME 
+FROM CUSTOMER LEFT JOIN CUSTOMER_ORDER
+ON CUSTOMER.CUSTOMER_ID = CUSTOMER_ORDER.CUSTOMER_ID
+WHERE ORDER_ID IS NULL;
+```
+## Other JOIN Types
+### RIGHT JOIN and OUTER JOIN
+Not featured in SQLite due to their highly niche nature.
+
+## Joining Multiple Tables
+```
+SELECT ORDER_ID, customer.CUSTOMER_ID, name, 
+street_address,city,state,zip,order_date,product_id,description, order_qty
+FROM CUSTOMER 
+INNER JOIN CUSTOMER_ORDER 
+ON CUSTOMER.CUSTOMER_ID = CUSTOMER_ORDER.CUSTOMER_ID 
+INNER JOIN PRODUCT
+ON CUSTOMER_ORDER.PRODUCT_ID=PRODUCT.PRODUCT_ID ;
+```
+```
+SELECT ORDER_ID, customer.CUSTOMER_ID, name, 
+street_address,city,state,zip,order_date,product_id,description, order_qty, ORDER_QTY*PRICE AS REVENUE
+FROM CUSTOMER 
+INNER JOIN CUSTOMER_ORDER 
+ON CUSTOMER.CUSTOMER_ID = CUSTOMER_ORDER.CUSTOMER_ID 
+INNER JOIN PRODUCT
+ON CUSTOMER_ORDER.PRODUCT_ID=PRODUCT.PRODUCT_ID ;
+```
+## Grouping JOINs
+```
+SELECT ORDER_ID, customer.CUSTOMER_ID, name, 
+street_address,city,state,zip,order_date,product_id,description, order_qty, sum(ORDER_QTY*PRICE) AS totalRevenue
+FROM CUSTOMER 
+INNER JOIN CUSTOMER_ORDER 
+ON CUSTOMER.CUSTOMER_ID = CUSTOMER_ORDER.CUSTOMER_ID 
+INNER JOIN PRODUCT
+ON CUSTOMER_ORDER.PRODUCT_ID=PRODUCT.PRODUCT_ID 
+group by customer.customer_id, name;
+```
+```
+SELECT ORDER_ID, customer.CUSTOMER_ID, name, 
+street_address,city,state,zip,order_date,product_id,description, order_qty, sum(ORDER_QTY*PRICE) AS totalRevenue
+FROM CUSTOMER 
+left JOIN CUSTOMER_ORDER 
+ON CUSTOMER.CUSTOMER_ID = CUSTOMER_ORDER.CUSTOMER_ID 
+LEFT JOIN PRODUCT
+ON CUSTOMER_ORDER.PRODUCT_ID=PRODUCT.PRODUCT_ID 
+group by 2,3;
+```
+*NOTE*: Upon mixing INNER and LEFT join, INNER will always win and all the NULL values will get filtered out.
+```
+SELECT ORDER_ID, customer.CUSTOMER_ID, name, 
+street_address,city,state,zip,order_date,product_id,description, order_qty, coalesce(sum(ORDER_QTY*PRICE),0) AS totalRevenue
+FROM CUSTOMER 
+left JOIN CUSTOMER_ORDER 
+ON CUSTOMER.CUSTOMER_ID = CUSTOMER_ORDER.CUSTOMER_ID 
+LEFT JOIN PRODUCT
+ON CUSTOMER_ORDER.PRODUCT_ID=PRODUCT.PRODUCT_ID 
+group by 2,3;
+```
+# CHAPTER 9 **Database Design**
+## Creating a New Database and Tables
+```
+CREATE TABLE Company (
+    Company_Id   INTEGER      PRIMARY KEY AUTOINCREMENT,
+    Company_name VARCHAR (30) NOT NULL,
+    Description  VARCHAR (60),
+    Contact      INTEGER (10) NOT NULL
+);
+
+CREATE TABLE Attendees (
+    Attendee_Id Integer Primary key autoincrement,
+    Attendee_Name Varchar (60) NOT NULL,
+    Phone Integer (10) not null,
+    Email varchar (60),
+    VIP boolean default(0)
+);
+
+create table Room (
+    Room_Id integer primary key autoincrement,
+    Floor_No integer not null,
+    Seat_Capacity integer not null
+);
+
+create table Presentations (
+    Presentation_Id Integer primary key autoincrement,
+    Company_Id integer not null,
+    Room_Id integer not null,
+    Start_Time time,
+    End_Time time,
+    constraint fk_room
+    foreign key (room_id)
+    references room(room_id),
+   constraint fk_companies
+    foreign key(company_id)
+    references company(company_id)
+);
+
+create table Presentation_Attendance (
+    Ticket_Id integer primary key autoincrement,
+    Attendee_Id integer ,
+    Presentation_Id integer,
+   constraint fk_attendees
+    foreign key (attendee_id)
+    references attendees (attendee_id),
+   constraint fk_presentation
+    foreign key (presentation_id)
+    references presentation(presentation_id)
+
+);
+
+```
+## Creating Views
+```
+CREATE VIEW Presentation_VW AS
+    SELECT company.company_name AS name,
+           room.room_id AS room_no,
+           room.floor_no AS floor_no,
+           room.seat_capacity AS seat_capacity,
+           start_time,
+           end_time
+      FROM presentations
+           INNER JOIN
+           company ON company.company_id = presentations.company_id
+           INNER JOIN
+           room ON room.room_id = presentations.room_id;
+```
+
+# CHAPTER 10 **Managing Data**
+## Insert
+```
+insert into attendee (name)
+values('arzoo');
+```
+## Multiple Inserts
+```
+insert into attendee(name)
+values
+('b'),
+('c'),
+('d');
+```
+## Testing Foreign Keys
+### Correcting Mistake- Altering table company to have a foregin key attendee_id
+```
+pragma foreign_keys=off;
+begin transaction;
+alter table company rename to company_old;
+
+CREATE TABLE company (
+    Company_Id   INTEGER      PRIMARY KEY AUTOINCREMENT,
+    Company_Name VARCHAR (30) NOT NULL,
+    Description  VARCHAR (60),
+    Attendee_Id  INTEGER      NOT NULL
+                              REFERENCES Attendees (Attendee_Id),
+    CONSTRAINT fk_Attendees FOREIGN KEY (
+        Attendee_Id
+    )
+    REFERENCES Attendees (Attendee_Id) 
+);
+
+insert into company select * from company_old;
+commit;
+pragma foreign_keys=on;
+```
+
+### Testing Foreign Keys
+The following snippet throws error : FOREIGN KEY constraint failed
+```
+insert into company (company_name, attendee_id)
+values ('rexapp solutions', 4);
+```
+The following snippet works:
+```
+insert into company (company_name, attendee_id)
+values ('rexapp solutions', 3);
+```
+
+## DELETE
+It deletes all records
+```
+delete from company where description is null;
+```
+
+## TRUNCATE TABLE
+Not supported by sqlite but it is the preferred way of deleting records in MySQL,etc.
+```
+TRUNCATE TABLE ATTENDEES;
+```
+
+## UPDATE
+```
+update attendees set email=upper(email),
+attendee_name=upper(attendee_name)
+```
+
+```
+update attendees 
+set vip=1
+where attendee_id in (1,3);
+```
+
+##  DROP TABLE
+```
+drop table company_old;
+```

tempCodeRunnerFile.cpp

@@ -0,0 +1,10 @@
+#include <bits/stdc++.h>
+using namespace std;
+#define INF 999
+int V=8;
+int dist[8]={INF};
+
+int main(){
+
+    return 0;
+}