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Database Help

$10-30 USD

In Progress
Posted about 5 years ago

$10-30 USD

Paid on delivery
Consider the design of a database for a web site of jokes. Each joke is identified by a unique joke ID, a title, a description of the joke, the date the joke is posted, and a list of tags (each tag is a single word in lower cases). Only registered users can post, read, comment on jokes. Each registered user is identified by a user ID, a password, a first name, a last name, an email, the gender, and his/her age. A user can give at most one review for each joke, and on a particular day, the user can post at most 5 jokes and 5 reviews. Meanwhile, a joke can have no or many reviews. The review given by a user provides a score of “Excellent, Good, fair, or poor” and then a short remark. A user can modify an existing review that she/he gave earlier. One special user called “root” is designated as the administrator user. The root user can ban any other user into a black list. Once banned, a user will not be able to login into the system unless he/she is unbanned from the blacklist subsequently. In addition, each user has two dynamic lists: my favorite friends and my favorite jokes, which can be modified by the user when necessary by insert, delete or update . a). Draw an E-R diagram for the system, in particular, use arrows or thick lines to represent constraints appropriately. Write down your assumptions and justifications briefly and clearly. b). Translate the above E-R diagram into a relational model, i.e., write a set of CREATE TABLE statements. In particular, specify primary key, foreign key and other constraints whenever possible.
Project ID: 18647810

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8 proposals
Remote project
Active 5 yrs ago

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8 freelancers are bidding on average $39 USD for this job
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MYSQL MONSTER HERE!!! ABOUT ME- PLEASE CHECK FOLLOWING QUERIES. ******************************************************************** SELECT id, GROUP_CONCAT(res SEPARATOR ' ' ) AS result FROM (SELECT id, field1, lowcase, CONCAT(UPPER(SUBSTR(lowcase,1,1)),SUBSTR(lowcase,2, LENGTH(lowcase)-1)) res FROM( SELECT id, SUBSTRING_INDEX( SUBSTRING_INDEX(field1, ' ', n), ' ', -1 ) AS field1, LOWER(SUBSTRING_INDEX( SUBSTRING_INDEX(field1, ' ', n), ' ', -1 )) lowcase FROM tablea JOIN (SELECT 1 AS n UNION SELECT 2 AS n UNION SELECT 3 AS n UNION SELECT 4 AS n UNION SELECT 5 AS n UNION SELECT 6 AS n UNION SELECT 7 AS n UNION SELECT 8 AS n UNION SELECT 9 AS n UNION SELECT 10 AS n) numbers ON CHAR_LENGTH(field1) - CHAR_LENGTH(REPLACE(field1, ' ', '')) >= n - 1) tbl ORDER BY id ) tblB GROUP BY id *************************************** SELECT c.*, (c.client_income1+c.client_income2) AS Total_income, i.number_of_infractions, getInterpolate(c.client_income1+c.client_income2, i.number_of_infractions) AS fee FROM client_incomes c JOIN client_infractions i ON c.client_id=i.client_id ORDER BY c.client_id
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5.0 (38 reviews)
6.0
6.0
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I'm a Bsc degree holder in computer science. I have worked on many papers in report writing, research.I have read and understood your requirement and I know you will never regret, thank you.
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4.4 (17 reviews)
4.6
4.6
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i can do in 1 hour i can do in 1 houri can do in 1 houri can do in 1 houri can do in 1 houri can do in 1 houri can do in 1 houri can do in 1 houri can do in 1 houri can do in 1 houri can do in 1 hour
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3.0 (13 reviews)
4.7
4.7
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I'm working as a full stack software developer and i have 3 year experience i think i can handle the what is on your mind to make true. we can negotiate payments
$25 USD in 1 day
5.0 (2 reviews)
1.8
1.8
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Hi,I developer and Analist professional with experiency in PHP Framework Yii and Laravel Experiency in implementation and maintenance of plataform Moodle Manager Database Mysql,postgress,sql server Please me contact and I can help you best regards
$30 USD in 1 day
3.3 (4 reviews)
1.7
1.7
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Hello friend, I would like to work for your project, I have good knowledge in database in SQL Server. I hope you hire me. Thank you
$10 USD in 10 days
0.0 (0 reviews)
0.0
0.0
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I've been working as a Virtual Assistant for 4 years, 2 years in a company and 2 years freelancer. I can handle multiple task, ability to solve problems, produce high quality work. I strive to understand client needs and provide a great result. I can manage time effectively, I don't just want to meet deadlines rather, I prefer to complete the project well ahead of schedule. I am eager to try new things and a quick learner, able to follow instructions and directions in order to complete projects. I can help you grow your business, give and taking back your time management, improve your sales and productivity and give extra earnings. I can give my initiative and dedication. I am determined and dedicate myself to bring my expertise in your business.
$10 USD in 1 day
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Hi I work in top Chinese stat-owned Enterprise, professional in data immigration & data query. expert in mySQL, postgreSQL, I have experiences in processed billions of data every day.
$25 USD in 1 day
0.0 (0 reviews)
0.0
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saint clair shores, United States
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