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#philosophy-of-social-science
Th e questions distinctive of the philosophy of the social sciences are encompassed within three broad themes: normativity, naturalism, and reduc- tionism

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Convert all the Entities in the diagram to tables.

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Convert ER Diagram into Tables - Generalization - Specialization - Aggregation - Transform ER Diagram into Tables
am takes their own depiction here. Consider the ER diagram below and will see how it is converted into tables, columns and mappings. The basic rule for converting the ER diagrams into tables is <span>Convert all the Entities in the diagram to tables. All the entities represented in the rectangular box in the ER diagram become independent tables in the database. In the below diagram, STUDENT, COURSE, LECTURER and SUBJECTS forms indiv




All single valued attributes of an entity is converted to a column of the table

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Convert ER Diagram into Tables - Generalization - Specialization - Aggregation - Transform ER Diagram into Tables
he entities represented in the rectangular box in the ER diagram become independent tables in the database. In the below diagram, STUDENT, COURSE, LECTURER and SUBJECTS forms individual tables. <span>All single valued attributes of an entity is converted to a column of the table All the attributes, whose value at any instance of time is unique, are considered as columns of that table. In the STUDENT Entity, STUDENT_ID, STUDENT_NAME form the columns of STUDENT t




Key attribute in the ER diagram becomes the Primary key of the table.

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Convert ER Diagram into Tables - Generalization - Specialization - Aggregation - Transform ER Diagram into Tables
as columns of that table. In the STUDENT Entity, STUDENT_ID, STUDENT_NAME form the columns of STUDENT table. Similarly, LECTURER_ID, LECTURER_NAME form the columns of LECTURER table. And so on. <span>Key attribute in the ER diagram becomes the Primary key of the table. In diagram above, STUDENT_ID, LECTURER_ID, COURSE_ID and SUB_ID are the key attributes of the entities. Hence we consider them as the primary keys of respective table. Declare the forei




Declare the foreign key column, if applicable.

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Convert ER Diagram into Tables - Generalization - Specialization - Aggregation - Transform ER Diagram into Tables
Primary key of the table. In diagram above, STUDENT_ID, LECTURER_ID, COURSE_ID and SUB_ID are the key attributes of the entities. Hence we consider them as the primary keys of respective table. <span>Declare the foreign key column, if applicable. In the diagram, attribute COURSE_ID in the STUDENT entity is from COURSE entity. Hence add COURSE_ID in the STUDENT table and assign it foreign key constraint. COURSE_ID and SUBJECT_ID




Any multi-valued attributes are converted into new table.

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Convert ER Diagram into Tables - Generalization - Specialization - Aggregation - Transform ER Diagram into Tables
n it foreign key constraint. COURSE_ID and SUBJECT_ID in LECTURER table forms the foreign key column. Hence by declaring the foreign key constraints, mapping between the tables are established. <span>Any multi-valued attributes are converted into new table. A hobby in the Student table is a multivalued attribute. Any student can have any number of hobbies. So we cannot represent multiple values in a single column of STUDENT table. We need




Any composite attributes are merged into same table as different columns.

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Convert ER Diagram into Tables - Generalization - Specialization - Aggregation - Transform ER Diagram into Tables
uld not create any redundancy or anomalies in the system. Hence we create a separate table STUD_HOBBY with STUDENT_ID and HOBBY as its columns. We create a composite key using both the columns. <span>Any composite attributes are merged into same table as different columns. In the diagram above, Student Address is a composite attribute. It has Door#, Street, City, State and Pin. These attributes are merged into STUDENT table as individual columns. One can




One can ignore derived attribute, since it can be calculated at any time.

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Convert ER Diagram into Tables - Generalization - Specialization - Aggregation - Transform ER Diagram into Tables
fferent columns. In the diagram above, Student Address is a composite attribute. It has Door#, Street, City, State and Pin. These attributes are merged into STUDENT table as individual columns. <span>One can ignore derived attribute, since it can be calculated at any time. In the STUDENT table, Age can be derived at any point of time by calculating the difference between DateOfBirth and current date. Hence we need not create a column for this attribute. I




Weak entity is also represented as table.

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Convert ER Diagram into Tables - Generalization - Specialization - Aggregation - Transform ER Diagram into Tables
verting ER diagram into tables and columns, and assigning the mapping between the tables. Table structure at this would be as below: Let us see some of the special cases. Converting Weak Entity <span>Weak entity is also represented as table. All the attributes of the weak entity forms the column of the table. But the key attribute represented in the diagram cannot form the primary key of this table. We have to add a foreign




We have to add a foreign key column, which would be the primary key column of its strong entity. This foreign key column along with its key attribute column forms the primary key of the table.

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Convert ER Diagram into Tables - Generalization - Specialization - Aggregation - Transform ER Diagram into Tables
ty is also represented as table. All the attributes of the weak entity forms the column of the table. But the key attribute represented in the diagram cannot form the primary key of this table. <span>We have to add a foreign key column, which would be the primary key column of its strong entity. This foreign key column along with its key attribute column forms the primary key of the table. In our example above, SUBJECTS is the weak entity. Hence, we create a table for it. Its attributes SUBJECT_ID and SUBJECT_NAME forms the column of this table. Although SUBJECT_ID is rep




#Conversion #ER #Table
SUBJECTS is the weak entity. Hence, we create a table for it. Its attributes SUBJECT_ID and SUBJECT_NAME forms the column of this table

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Convert ER Diagram into Tables - Generalization - Specialization - Aggregation - Transform ER Diagram into Tables
ign key column, which would be the primary key column of its strong entity. This foreign key column along with its key attribute column forms the primary key of the table. In our example above, <span>SUBJECTS is the weak entity. Hence, we create a table for it. Its attributes SUBJECT_ID and SUBJECT_NAME forms the column of this table. Although SUBJECT_ID is represented as key attribute in the diagram, it cannot be considered as primary key. In order to add primary key to the column, we have to find the foreign key f




#Conversion #ER #Table
COURSE is the strong entity related to SUBJECT. Hence the primary key COURSE_ID of COURSE is added to SUBJECT table as foreign key.

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Convert ER Diagram into Tables - Generalization - Specialization - Aggregation - Transform ER Diagram into Tables
le. Although SUBJECT_ID is represented as key attribute in the diagram, it cannot be considered as primary key. In order to add primary key to the column, we have to find the foreign key first. <span>COURSE is the strong entity related to SUBJECT. Hence the primary key COURSE_ID of COURSE is added to SUBJECT table as foreign key. Now we can create a composite primary key out of COURSE_ID and SUBJECT_ID. Representing 1:1 relationship Imagine SUBJECT is not a weak entity, and we have LECTURER teaches SUBJECT relat




#Conversion #ER #Table
in this case both the participating entities are converted into tables, and a new table is created for the relation between them. Primary keys of entity tables are added into new table to form the composite primary key. We can add any additional columns, if present as attribute of the relation in ER diagram.

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Convert ER Diagram into Tables - Generalization - Specialization - Aggregation - Transform ER Diagram into Tables
eate one more table for the relation ‘Enrolment’ and name it as STUD_COURSE. Add the primary keys of COURSE and STUDENT into it, which forms the composite primary key of the new table. That is, <span>in this case both the participating entities are converted into tables, and a new table is created for the relation between them. Primary keys of entity tables are added into new table to form the composite primary key. We can add any additional columns, if present as attribute of the relation in ER diagram. Self Referencing 1:N relation Consider the example of HOD and Lecturers. Here one of the Lecturers is a HOD of the department. i.e.; one HOD has multiple lecturers working with him. In




Flashcard 4293235182860

Tags
#Conversion #ER #Table
Question

Convert Entities to tables

- True

- False

Answer
Convert all the Entities in the diagram to tables.


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Convert ER Diagram into Tables - Generalization - Specialization - Aggregation - Transform ER Diagram into Tables
am takes their own depiction here. Consider the ER diagram below and will see how it is converted into tables, columns and mappings. The basic rule for converting the ER diagrams into tables is <span>Convert all the Entities in the diagram to tables. All the entities represented in the rectangular box in the ER diagram become independent tables in the database. In the below diagram, STUDENT, COURSE, LECTURER and SUBJECTS forms indiv







Flashcard 4293237017868

Tags
#Conversion #ER #Table
Question
[default - edit me]
Answer
All single valued attributes of an entity is converted to a column of the table


statusnot learnedmeasured difficulty37% [default]last interval [days]               
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scheduled repetition interval               last repetition or drill
Convert ER Diagram into Tables - Generalization - Specialization - Aggregation - Transform ER Diagram into Tables
he entities represented in the rectangular box in the ER diagram become independent tables in the database. In the below diagram, STUDENT, COURSE, LECTURER and SUBJECTS forms individual tables. <span>All single valued attributes of an entity is converted to a column of the table All the attributes, whose value at any instance of time is unique, are considered as columns of that table. In the STUDENT Entity, STUDENT_ID, STUDENT_NAME form the columns of STUDENT t







Flashcard 4293978623244

Question
مﻼﺳ / Slam
Answer
[default - edit me]


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Flashcard 4293980458252

Question
[default - edit me]
Answer
Olá!


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