Please discuss these questions with your partners and post your answers as a comment on this gist when you are finished.
Mohamad Sheikh Alshabab, Najwan, Farah, Lunar
0- SQL is a query programming language that manages RDBMS. MySQL is a relational database management system that uses SQL.
1- DBMS: A database management system (DBMS) is system software for creating and managing databases. A DBMS makes it possible for end users to create, protect, read, update and delete data in a database, It handles tasks like data storage, retrieval, and management.
Types of DBMS:
It also has a hierarchical structure, but the data is organized like a graph and it is allowed to have more than one parent for one child record.
2-
Returns matching rows from both tables.
Example: SELECT * FROM table1 INNER JOIN table2 ON table1.column = table2.column;
Returns all rows from the left table and matching rows from the right table.
Example: SELECT * FROM table1 LEFT JOIN table2 ON table1.column = table2.column;
Returns all rows from the right table and matching rows from the left table.
Example: SELECT * FROM table1 RIGHT JOIN table2 ON table1.column = table2.column;
Returns all rows when there is a match in either table.
Example: SELECT * FROM table1 FULL JOIN table2 ON table1.column = table2.column;
Returns the Cartesian product of both tables.
Example: SELECT * FROM table1 CROSS JOIN table2;
Joins a table with itself using aliases.
Example: SELECT e1.name, e2.name FROM employees e1 INNER JOIN employees e2 ON e1.manager_id = e2.employee_id;
3- is a column in a relational database table that's distinctive for each record.
4- SQL Arithmetic Operators · SQL Bitwise Operators · SQL Comparison Operators · SQL Compound Operators · SQL Logical Operators
5- Group functions, also known as aggregate functions, are essential in SQL for performing calculations on sets of values and summarizing data in a result set. These functions operate on a group of rows and return a single value for each group. The need for group functions in SQL arises from several reasons:
Summarizing Data:
Group functions allow you to perform calculations on a set of values within a specific group. For example, you can calculate the total sales, average salary, or maximum value for each group.
Statistical Analysis:
SQL group functions provide statistical measures like average, standard deviation, variance, etc., which are useful for analyzing data distributions within groups.
Data Aggregation:
They help in aggregating data from multiple rows into a single result. This is particularly important when working with large datasets where summarizing information is necessary for meaningful analysis.
Reporting:
Group functions are commonly used in generating reports where aggregated data is presented. For instance, you might want to show the total sales for each product category or the average score for each student in a class.
Data Analysis and Business Intelligence:
In the context of data analysis and business intelligence, group functions play a crucial role in extracting meaningful insights from datasets. They enable users to analyze trends, patterns, and summarize key metrics.
Efficiency:
Group functions improve the efficiency of data retrieval and analysis by allowing you to perform calculations directly in the database engine. This reduces the amount of data transferred between the database and the application, leading to better performance.
Combining with GROUP BY Clause:
Group functions are typically used in conjunction with the GROUP BY clause, which divides the result set into groups based on one or more columns. This facilitates the aggregation of data within each group.
Flexibility in Analysis:
Group functions provide flexibility in the type of analysis you can perform, whether it's finding the minimum or maximum value, calculating the average, or counting the number of occurrences within each group.
Commonly used SQL group functions include:
COUNT(): Counts the number of rows in a group.
SUM(): Calculates the sum of values in a group.
AVG(): Calculates the average of values in a group.
MIN(): Finds the minimum value in a group.
MAX(): Finds the maximum value in a group.
In summary, group functions are indispensable in SQL for summarizing, analyzing, and extracting meaningful information from datasets, making them a fundamental aspect of database querying and reporting.
6- Relationships are the established associations between two or more tables. Relationships are based on common fields from more than one table, often involving primary and foreign keys.One-to-One (1:1),One-to-Many (1:N),Many-to-Many (M:N).
Jana AbuHaltam, Musab Sakhreyah, Ahmad Mash, Lina Abumahfood ,Rinad Abu Qauod
Q0.SQL is a query programming language . MySQL is a relational database management system that uses SQL.
Q1 (DBMS) is a computer program designed to manage a large amount of structured data, and run operations on the desired data requested by the users.types include integer, float, characters, strings, and arrays.
Q2 Different Types of SQL JOINs (INNER) JOIN : Returns records that have matching values in both tables.
LEFT (OUTER) JOIN : Returns all records from the left table, and the matched records from the right table.
RIGHT (OUTER) JOIN : Returns all records from the right table, and the matched records from the left table.
Q3 A primary key is the column or columns that contain values that uniquely identify each row in a table
Q4 1) Arithmetic Operators:
(Greater than)
<= (Less than or equal to)
= (Greater than or equal to)
Logical Operators:
AND (Logical AND)
OR (Logical OR)
NOT (Logical NOT)
Bitwise Operators:
• Perform operations on bit patterns of integer values.
• Operators: & (bitwise AND), | (bitwise OR), ^ (bitwise XOR), ~ (bitwise NOT), << (left shift), >> (right shift)
String Operators:
• Manipulate and compare string values.
• Operators: || (concatenation), LIKE (pattern matching)
Compound Operators:
• Combine assignment and arithmetic or bitwise operations.
• Operators: +=, -=, *=, /=, %=, &=, |=, ^=, <<=, >>=
Other Operators:
• BETWEEN: Checks if a value is within a specified range.
• IN: Checks if a value is present in a list of values.
• IS NULL: Checks if a value is null.
• EXISTS: Checks if a subquery returns any rows.
Q5 1. Summarizing Data
2. Data Analysis
3. Statistical Calculations
4. Data Reporting
5. Performance Optimization
6. Efficient Data Retrieval
Q6 a relationship refers to the connection between two or more tables in a relational database. These relationships define how data in one table is related to data in another table.
Rinad Abu Qauod 6:37 PM
6- a relationship refers to the connection between two or more tables in a relational database. These relationships define how data in one table is related to data in another table.
There are three main types of relationships:
1- One-to-One (1:1) Relationship
2- One-to-Many (1:N) Relationship
3- Many-to-Many (N:N) Relationship
Q1 SQL is a query language, MySQL is a relational database that uses SQL to query a database
Q2 DBMS Database Management Systems. It is a software system that allows users to store, modify, and extract data from a database.
Types of DBMS:
1-Relational database.
2-Object oriented database.
3-Hierarchical database.
4-Network database.
Q3 A primary key is a field in a database table that uniquely identifies each record in the table.
Q4
Types of SQL operators:
1- comparison operators ( =, <, >, <=, >=, <>)
2- logical operators (AND, OR, NOT)
3- arithmetic operators (+, -, *, /)
4- string operators (LIKE, IN, BETWEEN)
Q5 SQL are used to perform calculations
Q6
Tables Relations in SQL Server:
One-to-One,
One-to-Many,
Many-to-Many,
Team: Hayder, Hakeema, Ramah, Osama
Q0: The difference is SQL is a programming language which MySQL, which is a open-sourced software, uses. SQL is mainly used for storing, manipulating and retrieving data in a RDB, while MySQL is a open source DB management system, That allows managing relational databases,
Q1: DBMS is Database management system software, which is a computer program designed to manage a large amount of structured data, and run operations on the desired data requested by the users. There are different types of DBMS, some of them are: Relation Databases, Object Oriented Databases, Hierarchical Databases, Network Databases.
Q2: The different types of joins are: INNER JOIN, OUTER JOIN, CROSS JOIN, SELF JOIN. Examples of them:
INNER JOIN: Returns only the rows where there is a match in both tables.
SELECT employees.employee_id, employees.employee_name, departments.department_name
FROM employees
INNER JOIN departments ON employees.department_id = departments.department_id;
OUTER JOIN: Returns all rows from the left table (For this example) and the matched rows from the right table. If there is no match, NULL values are returned for columns from the right table.
SELECT customers.customer_id, customers.customer_name, orders.order_id
FROM customers
LEFT JOIN orders ON customers.customer_id = orders.customer_id;
CROSS JOIN: is used to generate the Cartesian product of two tables, creating all possible combinations of rows between them without any specific matching condition.
SELECT students.student_id, students.student_name, subjects.subject_id, subjects.subject_name
FROM students
CROSS JOIN subjects;
SELF JOIN: A self join is used to combine rows within a table, treating it as if it were two separate tables.
SELECT e.employee_name AS employee, m.employee_name AS manager
FROM employees e
LEFT JOIN employees m ON e.manager_id = m.employee_id;
Q3: A primary key, is a column in a relational database table that's distinctive for each record. It's a unique identifier. A relational database must have only one primary key. Every row of data must have a primary key value and none of the rows can be null.
Q4: Some of the SQL operators are: Arithmetic Operators, Bitwise Operators, Comparison Operators, Compound Operators, Logical Operators.
Q5: Very basically, the GROUPING function in SQL helps in dealing with complex queries.
Q6: a relationship refers to the association between tables in a database. And they are: One-to-Many, Many-to-Many, One-to-One
Examples of each:
One-to-Many: Customer that has many Order
One-to-One: Every person has only one ID, or passport
Many-to-Many: Many Products that have Many Customers
**### Team Group:
Lubna Abdelkhaliq
Nour Kayyali
Wajd Al-Kayyali
Ammar Kolko
SQL is a query programming language that manages RDBMS.
MySQL is a relational database management system that uses SQL.
SQL is primarily used to query and operate database systems.
MySQL allows you to handle, store, modify and delete data and store data in an organized way
A database management system (DBMS) is a computer program designed to manage a large amount of structured data, and run operations on the desired data requested by the users
There are three main types of DBMS data models: relational, network, and hierarchical.
Relational data model: Data is organized as logically independent tables.
Network data model: All entities are organized in graphical representations.
Hierarchical data model: Data is organized into a tree-like structure.
Purpose: Retrieves records that have matching values in both tables.
Example: SELECT customers.customer_id, orders.order_date
FROM customers
INNER JOIN orders
ON customers.customer_id = orders.customer_id;
Result: Returns only customers who have placed orders, with their corresponding order dates.
Purpose: Retrieves all records from the left table, and the matched records from the right table. If there's no match in the right table, NULL values are returned for those columns.
Example :SELECT customers.customer_id, orders.order_date
FROM customers
LEFT JOIN orders
ON customers.customer_id = orders.customer_id;
Result: Returns all customers, including those without orders (showing NULL for order_date).
3)Right Outer Join:
Purpose: Retrieves all records from the right table, and the matched records from the left table. If there's no match in the left table, NULL values are returned for those columns.
Example :SELECT customers.customer_id, orders.order_date
FROM customers
RIGHT JOIN orders
ON customers.customer_id = orders.customer_id;
Result: Returns all orders, including those without a corresponding customer (showing NULL for customer_id).
Purpose: Retrieves all records from both tables, including unmatched rows, filling in NULL values where there's no match.
Example :SELECT customers.customer_id, orders.order_date
FROM customers
FULL JOIN orders
ON customers.customer_id = orders.customer_id;
Result: Returns all customers and all orders, even if they don't have a corresponding match in the other table.
A primary key is a special column or set of columns in a database table that uniquely identifies each row in that table
***key characteristics of primary keys:
-Uniqueness: Each value in the primary key column(s) must be unique within the table. This means no two rows can have the same primary key value.
-Not Null: Primary key columns cannot contain null values. They must always have a value to ensure they can uniquely identify each row.
-Single Primary Key per Table: A table can have only one primary key.
***Purpose of Primary Keys:
Preventing Duplicates, Creating Relationships
Logical // Compound // Comparison // Bitwise // Arithmetic https://www.w3schools.com/sql/sql_operators.asp
In SQL, the GROUPING function is a very useful tool when dealing with complex queries that involve grouping sets, rollup, and cube operations. Group functions are built-in SQL functions that operate on groups of rows and return one value for the entire group. These functions are: COUNT, MAX, MIN, AVG, SUM, DISTINCT
In SQL, a relationship refers to a connection between two tables based on a common column. It is established using foreign keys, which link the data in one table to the data in another. This helps maintain data integrity and enables queries that involve data from multiple tables. There are different types of relationships, such as one-to-one, one-to-many, and many-to-many, each serving specific data modeling needs.
SQL serves as a query programming language designed for managing Relational Database Management Systems (RDBMS). MySQL, in turn, is an RDBMS that employs SQL for its operations. The primary function of SQL revolves around querying and manipulating database systems. MySQL, leveraging SQL, facilitates the handling, storage, modification, and deletion of data, ensuring organized data storage.
A Database Management System (DBMS) is essentially a computerized system for maintaining and organizing data. Users of the system are provided with tools to perform various operations, allowing for the manipulation of data within the database or the management of the database structure. DBMSs are classified based on their data structures or types.
A. Object-Oriented Database:
B. Hierarchical Database:
C. Network Database:
A primary key in SQL refers to either a single field or a group of fields or columns within a table that serves the crucial function of uniquely identifying each row. In essence, it is a designated column that exclusively accepts distinct values for every individual row.
A. Arithmetic SQL Operators:
B. Comparison SQL Operators:
C. Logical SQL Operators:
Group functions in SQL, particularly the GROUPING function, play a crucial role in managing complex queries involving grouping sets, rollup, and cube operations. This function helps differentiate between NULLs representing the absence of data and those present in super-aggregate results. By returning 1 for super-aggregate rows and 0 for regular grouped rows, the GROUPING function aids in clarifying results. Whether used in the SELECT statement, HAVING clause, or ORDER BY clause, this function requires a column name as an argument and must be paired with a GROUP BY clause. Its significance lies in distinguishing NULLs within super-aggregate rows, contributing to clearer and more comprehensible query outcomes.
A relationship refers to the established connections between two or more tables, typically based on shared fields. These connections often involve primary and foreign keys.
Abdullah Alawad / Hassan AbuGhareeb / hammam AbuShehadeh / Noor Alrai**
SQL: Structured Query is a query programming language that manages RDBMS.
MySQL is a relational database management system that uses SQL.
DBMS : Data Base management Systems : system that is used to store and mange data
Types: -Relational -Network DBMS -Object Oriented DB
(INNER) JOIN : Returns records that have matching values in both tables.
returns a result that includes rows from both left and right tables.
LEFT (OUTER) JOIN: Returns all records from the left table, and the matched records from the right table.
You can imagine it with a Venn diagram with two circles, with the resulting table being the green highlighted part which includes
both the common/overlapping part, and the rest of the left circle.
RIGHT (OUTER) JOIN: Returns all records from the right table, and the matched records from the left table.
The RIGHT OUTER JOIN selects data from the right table (Table B) and matches this data with the rows from the left table
(Table A). The RIGHT JOIN returns a result set that includes all rows in the right table
Self Join: join a table to itself, can be viewed as a join of two copies of the same table.
Cross Join (also known as a cartesian join): returns all combinations of rows from each table.
CROSS JOIN joins every row from the first table with every row from the second table and its result comprises all combinations of records
in two tables.
PK: is a field that uniquely identify each record in a table
Arithmetic / Comparison / Bitwise / Logical / Compound
COUNT(): Counts the number of rows in a set.
SUM(): Calculates the sum of numeric values in a set.
AVG(): Computes the average of numeric values in a set.
MIN(): Finds the minimum value in a set.
MAX(): Finds the maximum value in a set.
The need is to summarize Data in one value
Relations the established associations between two or more tables
One to One:
One to Many
Many to Many
Gorgees, Dana
What is the difference between SQL and MySQL?
What do you mean by DBMS? What are its different types?
What are the types of joins in SQL? Give an example for each one:
What is a Primary key?
What are the different operators available in SQL?
Team : Mohammad,Diala,Yassin,malak,feda
Q0: SQL is a programming language you can use to store and process information in a relational database. MySQL is the most widely adopted open-source relational database. Both technologies work together so that you can store and process data in structured tables with rows and columns. MySQL is the underlying technology that stores the data, while SQL is the language you use to read, modify, and delete that data.
Q1- DBMS : Database Management Systems is a collection of programs used for managing data and simultaneously it supports different types of users to create, manage, retrieve, update and store information.
Relational database:is a system where data is organized in two-dimensional tables using rows and columns.
Object Oriented Database: It is a system where information or data is represented in the form of objects which is used in object-oriented programming.
Hierarchical Database: It is a system where the data elements have a one to many relationship (1: N). Here data is organized like a tree which is similar to a folder structure in your computer system.
Network database is a system where the data elements maintain one to one relationship (1: 1) or many to many relationship (N: N).It also has a hierarchical structure, but the data is organized like a graph and it is allowed to have more than one parent for one child record.
Q2:(INNER) JOIN: Returns records that have matching values in both tables
LEFT (OUTER) JOIN: Returns all records from the left table, and the matched records from the right table
RIGHT (OUTER) JOIN: Returns all records from the right table, and the matched records from the left table
FULL (OUTER) JOIN: Returns all records when there is a match in either left or right table
Q3: the column or columns that contain values that uniquely identify each row in a table.
Q4:1- SQL Arithmetic Operators 2-SQL Bitwise Operators 3-SQL Comparison Operators 4- SQL Compound Operators 5- SQL Logical Operators
Q5: they are built-in SQL functions that operate on groups of rows and return one value for the entire group.COUNT, MAX, MIN, AVG, SUM, DISTINCT
Q6:an association between tables. Those associations create using join statements to retrieve data. It is a condition that exists between two database tables in which one table contains a foreign key that references the primary key of the other tables.
one-to-one.
one-to-many.
many-to-many.