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@@ -870,49 +870,51 @@
 		  :LOGBOOK:
 		  CLOCK: [2023-06-04 Sun 16:27:23]--[2023-06-04 Sun 16:54:55] => 00:27:32
 		  :END:
-			- LATER Block 1
+			- DONE Block 1
+			  deck:: 2023t1/database
+			  collapsed:: true
 				- DONE DBMS
 					- Database is :-> a shared collection of logically related data (and a description of this data), designed to meet the information needs of an organization.
-					  id:: 64895ec0-d724-4159-a95d-657afd171c29
+					  id:: 648974ba-3221-48b2-8f9c-2d9275174f48
 					- Table :-> A collection of related data organized into rows (also called records) and columns (also called fields).
-					  id:: 64895ec0-2290-4f62-8711-45e99803c82e
+					  id:: 648974ba-7b5a-4cff-8d21-3bcc7e0c1fe8
 					- Row/Record :-> A single set of data in a table, representing a specific instance or entity.
-					  id:: 64895ec0-12a9-402d-8c1d-64c40e169bb2
+					  id:: 648974ba-d192-4027-945a-9c6113ac218f
 					- Column/Field :-> A specific attribute or data element within a table.
-					  id:: 64895ec0-2aed-4aa8-a34f-446fd7715db6
+					  id:: 648974ba-89e7-434a-b242-68a1ea3f7f6b
 					- Primary Key :-> A unique identifier for each row/record in a table. It ensures the integrity and uniqueness of the data.
-					  id:: 64895ec0-7339-477c-b765-b12fd18e9df4
+					  id:: 648974ba-611e-4d5c-849b-9cd57b7bddb9
 					- Foreign Key :-> A field in one table that refers to the primary key in another table, establishing a relationship between the two tables.
-					  id:: 64895ec0-75e5-4378-aa9c-b4af6d7d37c9
+					  id:: 648974ba-bc0d-4b78-a8cb-7a081ca1b2ac
 					- Relationship :-> The connection between tables based on common data values, such as primary and foreign keys.
-					  id:: 64895ec0-ab80-4eed-bb91-0911b1954368
+					  id:: 648974ba-851d-42a7-95c1-2619fed22d3a
 					- Normalization :-> The process of organizing and structuring a database design to eliminate redundancy and improve data integrity.
-					  id:: 64895ec0-8b79-4172-8cad-25e4edada659
+					  id:: 648974ba-53b0-4176-b67b-cd51d1ea09c6
 					- Index :-> A data structure that improves the retrieval speed of data from a database table by creating a quick reference to the location of the data.
-					  id:: 64895ec0-f3cd-4625-b2ca-6e94f870b34d
+					  id:: 648974ba-2246-42c3-aa0c-7609107af7c5
 					- Query :-> A request for data or information from a database, usually written using Structured Query Language (SQL).
-					  id:: 64895ec0-df79-46a4-8fb2-09b34a414c9c
+					  id:: 648974ba-4b3e-4f99-90fd-b4c9a1a43a53
 					- SQL (Structured Query Language) :-> A programming language used to manage and manipulate relational databases. It allows you to create, modify, and retrieve data from databases.
-					  id:: 64895ec0-4de4-4cfd-8042-7f92458a8a26
+					  id:: 648974ba-a844-4e21-a1ca-e0b26668f1b7
 					- CRUD Operations :-> An acronym for Create, Read, Update, and Delete operations, which are the basic operations used to manage data in a database.
-					  id:: 64895ec0-77ed-4253-947e-2a54c4235a05
+					  id:: 648974ba-34d4-49df-91c9-b44b018120c6
 					- ACID (Atomicity, Consistency, Isolation, Durability) :-> A set of properties that guarantee the reliability and integrity of database transactions.
-					  id:: 64895ec0-e18b-4340-8a24-98b2cbaec1fd
+					  id:: 648974ba-4174-45b7-8903-38ffea39a200
 					- Data Integrity :-> The accuracy, consistency, and reliability of data stored in a database.
-					  id:: 64895ec0-023b-47dc-96bd-7a4c52fd9717
+					  id:: 648974ba-7797-4a43-b644-f0780da5121b
 					- Database Schema :-> The structure or blueprint of a database, defining the tables, fields, relationships, and constraints.
-					  id:: 64895ec0-0c9b-49fc-923d-264841105690
+					  id:: 648974ba-7b5c-45d1-ac86-ef7211c9672a
 					- Database Management System (DBMS) :-> Software that provides an interface to interact with databases, managing their creation, modification, and retrieval.
-					  id:: 64895ec0-60c1-468f-bc13-bd65c736a682
+					  id:: 648974ba-627d-463c-9237-56777d45b8af
 				- DONE basic concepts of Relational model
 					- A data model :- > a graphical description of the
 					  components of database.
 					- A relation, is :-> a two-dimensional table arranged in columns and rows.
-					  id:: 64895ec0-a8ef-4e61-8e31-ce2b319a459b
+					  id:: 648974ba-40ec-4600-af39-d438a5f75339
 					- A relational database is :-> a collection of relations.
-					  id:: 64895ec0-4f99-4abd-a0f1-a0707ff20bd7
+					  id:: 648974ba-c76d-4f2b-a8ad-ef1ad3a16b2c
 					- Candidate Key #flashcard
-					  id:: 64895ec0-44d2-4816-9201-492149a1e26e
+					  id:: 648974ba-a2f3-43a1-a5ea-c170c68314e1
 						- A set of attributes that uniquely identifies a tuple within a
 						  relation.
 						- Uniqueness : In each tuple, candidate key uniquely identify
@@ -920,45 +922,44 @@
 						- Irreducibility: No proper subset of the candidate key has the
 						  uniqueness property.
 					- Primary Key #flashcard
-					  id:: 64895ec0-057c-49f6-8fd9-0fc599e49e0a
+					  id:: 648974ba-c5dc-44cb-8894-8f5838714f2a
 						- Candidate key selected to identify tuples uniquely within
 						  relation.
 					- Foreign Key #flashcard
-					  id:: 64895ec0-2bf4-4bf5-92f3-b266cfcce167
+					  id:: 648974ba-da05-48b6-aded-75d1ea5f1342
 						- Attribute, or set of attributes, within one relation that
 						  matches candidate key of some (possibly same) relation.
 					- Composite Key #flashcard
-					  id:: 64895ec0-7b2e-4031-97ca-157c1864ac1c
+					  id:: 648974ba-7242-4c00-b67b-5418c3f71e77
 						- A candidate key that consists of two or more attributes.
 					- Recursive Relationship #flashcard
-					  id:: 64895ec0-96f6-4a17-8d67-ddd8c7679066
+					  id:: 648974ba-eb07-4e80-a1c3-87555fb04d1a
 						- Relationship type where same entity type participates
 						  more than once in different roles.
 					- Multiplicity :-> number (or range) of possible
-					  id:: 64895ec0-3514-4e82-acf6-f25238116bb7
+					  id:: 648974ba-5d96-4c64-a1b0-e9e61aa3563a
 					  occurrences of an entity type that may relate to a
 					  single occurrence of an associated entity type
 					  through a particular relationship.
 					  ![image.png](../assets/image_1686723218703_0.png)
 						- Cardinality #flashcard
-						  id:: 64895ec0-4ad7-43f2-80fc-489bc0a07ec1
+						  id:: 648974ba-b24d-40a3-8669-9dbc85dedaf7
 							- Describes {{c1 maximum}} number of possible relationship occurrences for an entity participating in a given relationship type.
-							  id:: 64895ec0-e8d2-47e1-97b8-d81ed8d62f64
+							  id:: 648974ba-ea33-489d-bb7b-1951685babd0
 						- Participation #flashcard
-						  id:: 64895ec0-c4c3-400e-9cb6-08f722328773
+						  id:: 648974ba-6dc5-4805-9dfd-7db5a83efe3f
 							- Determines whether all or only some entity occurrences participate in a relationship.
 							- Gives the minimum number for an entity occurrences participating in a given relationship type.
 						- Ternary relationship #flashcard
-						  id:: 64895ec0-0897-4857-b763-0349ae186d62
+						  id:: 648974ba-9b7a-4543-b243-e7a78cfc8175
 							- a ternary relationship is not the same as three binary relationships!
-				- LATER basic concepts associated with Entity-Relationship(ER) model.
+				- DONE basic concepts associated with Entity-Relationship(ER) model.
 				- LATER Forming sql queries
-				  collapsed:: true
 					- DONE Review relational algebra https://www.geeksforgeeks.org/introduction-of-relational-algebra-in-dbms/
 					- LATER review lab2
 					- LATER SQL join
-			- LATER Block 2
+			- DONE Block 2
-				- LATER EER
+				- DONE EER
 					- Most useful additional concept of EER model:
 					  specialization/generalization.
 						- Specialization
@@ -973,6 +974,7 @@
 						  id:: 64896085-645b-408f-b17a-109b6cd82aeb
 						  specialization/generalization:
 							- participation constraints :-> Determines whether every member in superclass
+							  id:: 6489683b-319a-4173-a55b-6fa3b2c09aeb
 							  must participate as a member of a subclass.
 								- May be mandatory or optional. #flashcard
 								  id:: 648960d0-ae7f-4452-a1b9-cab8a9b13443
@@ -980,14 +982,10 @@
 									  member of subclass
 									- Optional: member of superclass may be member
 									  of subclass.
-							- disjoint constraints :-> Describes relationship between members of the
+							- disjoint constraints :-> Describes relationship between members of the subclasses and indicates whether member of a superclass can be a member of one, or more than one, subclass. #flashcard
-							  subclasses and indicates whether member of a
+							  id:: 6489683b-039f-4161-94b1-91177f713ee5
-							  superclass can be a member of one, or more than
+								- Disjoint: member of superclass is member of at most one subclass (or)
-							  one, subclass. #flashcard
+								- Nondisjoint: member of superclass can be member of more than one subclass (and)
-								- Disjoint: member of superclass is member of at
-								  most one subclass
-								- Disjoint: member of superclass is member of at
-								  most one subclass
 					- Superclass / Subclass
 						- Superclass :-> An entity type that includes one or more distinct
 						  id:: 64895f2f-b868-46ec-9d80-7079eaf3197d
@@ -1002,43 +1000,82 @@
 						- Subclass :-> A distinct subgrouping of occurrences of an entity
 						  id:: 64895f39-d886-436b-9afe-ba75d37c8b45
 						  type.
-						- When to use them? either one or both
+						- When to use them? either one or both #flashcard
-						  1. There are attributes that apply to some (but
+						  id:: 6489683b-7d47-4246-afdf-83fdb35a00f6
-						  not all) instances of an entity.
+							- There are attributes that apply to some (but not all) instances of an entity.
-						  2. The instances of a potential subclass
+							- The instances of a potential subclass participate in a relationship unique to that subclass.
-						  participate in a relationship unique to that
+					- DONE Designing databases
-						  subclass.
+						- Understand Database Design Methodology #flashcard
-				- LATER designing ER diagram
+							- Conceptual database design
+								- The process of constructing a model of the data used in an enterprise, independent of all physical considerations.
+							- Logical database design
+								- Maps the conceptual data model on to a logical model (e.g. relational), but independent of a particular DBMS and other physical considerations.
+							- Physical database design
+								- The process of producing a description of the implementation of the database (tailored to specific DBMS);
+						- general steps for Database Design Methodology. #flashcard
+							- Gather requirements
+							- Conceptual database design
+							- Logical database design
+							- Physical database design
+					- LATER SQL
+						- purpose and importance of SQL.
+						- retrieve data from database and formulate queries using SELECT and
+							- Use compound WHERE conditions.
+							- Sort query results using ORDER BY.
+							- Use aggregate functions.
+							- Group data using GROUP BY and HAVING.
+							- Join tables together.
+							- Use subqueries.
 			- DONE Block 3
 			  collapsed:: true
 				- DONE DB transaction management
-					- DONE ACID (Atomicity, Consistency, Isolation, Durability): A set of properties that guarantee the reliability and integrity of database transactions.
+					- DONE Deadlock and how it can be resolved. #flashcard
-						- Atomicity: The property that ensures a transaction is treated as a single, indivisible unit of work. It either executes all its operations successfully or rolls back to the initial state if any operation fails.
+					  id:: 64841da4-d8ce-46f5-bbe6-4dee620cde75
-						- Consistency: The property that ensures a transaction transforms the database from one consistent state to another consistent state. It maintains data integrity and adheres to defined business rules.
+						- A deadlock is a situation in which two or more transactions are unable
-						- Isolation: The property that ensures concurrent transactions do not interfere with each other. Each transaction operates in isolation until it completes, preventing interference or conflicts.
+						  to proceed because each is waiting for a resource held by the other,
-						- Durability: The property that ensures committed changes made by a transaction are permanently saved and will survive any subsequent system failures or crashes.
+						  resulting in a circular dependency and a system halt. It is a form of
+						  resource contention that can occur in concurrent systems, including
+						  database management systems.
+						- Example:
+					- Cascading rollback #flashcard
+					  id:: 64897f0b-dda6-4cc3-a9c3-cf630bcb0658
+						- Cascading Rollback: a transaction (T1) causes a
+						  failure and a rollback must be performed. Other
+						  transactions dependent on T1's actions must also
+						  be rollbacked, thus causing a cascading effect.
+						- One transaction's failure causes many to fail.
+					- DONE ACID (Atomicity, Consistency, Isolation, Durability): A set of properties that guarantee the reliability and integrity of database transactions. #flashcard
+					  id:: 64841da4-0055-4d34-9f61-1402ff068ec7
+					  collapsed:: true
+						- Atomicity: :-> The property that ensures a transaction is treated as a single, indivisible unit of work. It either executes all its operations successfully or rolls back to the initial state if any operation fails.
+						  id:: 64841d38-4ea9-4b76-8585-8b9de23915da
+						- Consistency: :-> The property that ensures a transaction transforms the database from one consistent state to another consistent state. It maintains data integrity and adheres to defined business rules.
+						  id:: 64841d38-2854-4dfb-8f21-0013fca66a0a
+						- Isolation: :-> The property that ensures concurrent transactions do not interfere with each other. Each transaction operates in isolation until it completes, preventing interference or conflicts.
+						  id:: 64841d38-fd2b-435e-bd45-3bf487a74b6f
+						- Durability: :-> The property that ensures committed changes made by a transaction are permanently saved and will survive any subsequent system failures or crashes.
+						  id:: 64841d38-950c-431e-8f28-ece98e230554
 					- DONE Concurrency control
-						- DONE Meaning of serialisability.
+						- DONE Meaning of serialisability. #flashcard
-						- DONE How locking can ensure serialisability.
+						  id:: 648428e1-5136-4d15-97c0-12087085b47f
+							- The objective of serialisability is to find nonserial schedules that are equivalent to some serial schedule. Such a schedule is called serialisable.
+						- DONE How locking can ensure serialisability. #flashcard
+						  id:: 64841da4-8812-405f-b49a-69eec9a069d2
 							- Locking achieves serializability by using locks to control access to
 							  shared resources (e.g., database objects like tables or rows) and
 							  prevent conflicts between concurrent transactions.
-						- DONE 2PL
+						- DONE 2PL #flashcard
+						  id:: 64841da4-eab4-40db-819f-249fe1437250
 							- In the 2PL protocol, transactions acquire and release locks on database
 							  objects (e.g., tables, rows) in two distinct phases: the growing phase
 							  and the shrinking phase.
-						- DONE Deadlock and how it can be resolved.
+						- DONE How timestamping can ensure serialisability. #flashcard
-							- A deadlock is a situation in which two or more transactions are unable
+						  id:: 64842000-07a7-4439-8ce6-7789e0a3358d
-							  to proceed because each is waiting for a resource held by the other,
-							  resulting in a circular dependency and a system halt. It is a form of
-							  resource contention that can occur in concurrent systems, including
-							  database management systems.
-						- DONE How timestamping can ensure serialisability.
 							- By using transaction timestamps and enforcing the read and write
 							  validation checks, concurrency control mechanisms can ensure that
 							  transactions are executed in a way that maintains data consistency and
 							  serializability.
-					- DONE Recovery Control
+					- ==DONE Recovery Control==
 						- DONE Some causes of database failure.
 							- System crashes, resulting in loss of main memory.
 							- Power failures
@@ -1047,20 +1084,23 @@
 							- Natural physical disasters.
 							- User mistakes.
 							- Sabotage.
-						- DONE Purpose of transaction log file.
+						- DONE Purpose of transaction log file. #flashcard
+						  id:: 64841f8f-5a9e-4f22-8f51-47931937998a
 							- Contains information about all updates to
 							  database:
 								- Transaction records.
 								- Checkpoint records.
 								- Often used for other purposes (for example, auditing).
 							- For autiding
-						- DONE Purpose of checkpointing.
+						- DONE Purpose of checkpointing. #flashcard
+						  id:: 64841f91-1d24-49f6-9f83-7c8b565c647f
 							- When failure occurs, redo all transactions that
 							  committed since the checkpoint and undo all
 							  transactions active at time of crash.
 				- DONE Normalization
 				  background-color:: yellow
-					- DONE Functional dependencies [g4g](https://www.geeksforgeeks.org/types-of-functional-dependencies-in-dbms/)
+					- DONE Functional dependencies [g4g](https://www.geeksforgeeks.org/types-of-functional-dependencies-in-dbms/) #flashcard
+					  id:: 648428e1-e704-4e23-941d-af9833de6f93
 						- In a relational database management, functional dependency is a concept
 						  that specifies the relationship between two sets of attributes where one
 						  attribute determines the value of another attribute. It is denoted as **X → Y**, where the attribute set on the left side of the arrow, **X** is called **Determinant** , and **Y** is called the **Dependent**.
@@ -1069,122 +1109,142 @@
 					  CLOCK: [2023-06-01 Thu 17:38:55]--[2023-06-01 Thu 17:38:56] => 00:00:01
 					  :END:
 					- DONE kinds of NF [tutorial](https://www.geeksforgeeks.org/normal-forms-in-dbms/)
-						- First Normal Form (1NF): This is the most basic level of
+						- First Normal Form (1NF): :-> This is the most basic level of
+						  id:: 648974ba-7334-4e73-a0ae-6b8fc6ec99ab
 						  normalization. In 1NF, each table cell should contain _only a single value, and each column should have a unique name_. The first normal form helps to eliminate duplicate data and simplify queries.
-						- Second Normal Form (2NF): 2NF eliminates redundant data by requiring that each _non-key attribute_ be dependent on the primary key. This means that _each column should be directly related to the primary key_, and not to other
+						- Second Normal Form (2NF): :->  2NF eliminates redundant data by requiring that each _non-key attribute_ be ==dependent on the primary key==. This means that _each column should be directly related to the primary key_, and not to other
+						  id:: 648974ba-cc9e-4cdf-a312-3af1bcab23f2
 						  columns.
-						- Third Normal Form (3NF): 3NF builds on 2NF by requiring
+						- Third Normal Form (3NF): :->  3NF builds on 2NF by requiring
-						  that _all non-key attributes are independent of each other._ This means that each column should be directly related to the primary key, and not to any other columns in the same table.
+						  id:: 648974ba-f325-450e-aede-9a7d92bcf888
-						- Boyce-Codd Normal Form (BCNF): BCNF is a stricter form of 3NF that ensures that each determinant in a table is a candidate key. In other words, BCNF ensures that _each non-key attribute is dependent only on the candidate key._
+						  that _all non-key attributes are **independent** of each other._ This means that each column should be **directly related to the primary key**, and not to any other columns in the same table.
+						- Boyce-Codd Normal Form (BCNF): :->  BCNF is a stricter form of 3NF that ensures that each determinant in a table is a candidate key. In other words, BCNF ensures that _each non-key attribute is dependent **only on the candidate key**._
+						  id:: 64842000-c15a-4b8f-95c3-d6c6e49e4af0
 						- Fourth Normal Form (4NF): 4NF is a further refinement of BCNF that ensures that _a table does not contain any multi-valued dependencies._
 						- Fifth Normal Form (5NF): 5NF is the highest level of normalization and involves decomposing a table into smaller tables to _remove data redundancy and improve data integrity._
-			- DONE Block 4
+					- Anomaly
+						- Update Anomalies #flashcard
+							- Insertion anomalies
+								- If there is a new row inserted in the table and it creates the 
+								  inconsistency in the table then it is called the insertion anomaly. For 
+								  example, if in the above table, we create a new row of a worker, and if 
+								  it is not allocated to any department then we cannot insert it in the 
+								  table so, it will create an insertion anomaly.
+							- Deletion anomalies
+								- If we delete some rows from the table and if any other information or 
+								  data which is required is also deleted from the database, this is called
+								   the deletion anomaly in the database. For example, in the above table, 
+								  if we want to delete the department number ECT669 then the details of 
+								  Rajesh will also be deleted since Rajesh's details are dependent on the 
+								  row of ECT669. So, there will be deletion anomalies in the table.
+							- Modification anomalies
+								- When we update some rows in the table, and if it leads to the 
+								  inconsistency of the table then this anomaly occurs. This type of 
+								  anomaly is known as an updation anomaly. In the above table, if we want 
+								  to update the address of Ramesh then we will have to update all the rows
+								   where Ramesh is present. If during the update we miss any single row, 
+								  then there will be two addresses of Ramesh, which will lead to 
+								  inconsistent and wrong databases.
+			- LATER Block 4
 				- DONE Distributed DBMS
-				  collapsed:: true
+					- DONE client server arch #flashcard
-					- DONE client server arch
+					  id:: 648974ba-9c11-4816-9d5e-0623dc4d4d45
-					  collapsed:: true
 						- Computers (client) connected over wired or wireless local area network (LAN)
 						- The database itself and the DBMS are stored on a central device called the database server, which is also connected to the network.
-					- Distributed Database
+					- Distributed Database #flashcard
-					  collapsed:: true
+					  id:: 648974ba-b13a-4f3f-8409-ea02b5ef5894
 						- A logically interrelated collection of shared data (and a description of this data), physically spread over a computer network.
-					- Distributed DBMS
+					- Distributed DBMS #flashcard
-					  collapsed:: true
+					  id:: 648974ba-997c-4f43-b2d6-d972cfc23d36
 						- Software system that permits the management of the distributed database and makes the distribution transparent to users.
-					- the key issues
+					- the key issues #flashcard
-					  collapsed:: true
+					  id:: 648974ba-4c63-4215-b420-d537c2a93675
 						- Fragmentation
 						- Allocation
 						- Replication
-					- importance and different types of fragmentation
+					- importance and different types of fragmentation #flashcard
-					  collapsed:: true
+					  id:: 648974ba-07aa-4c51-aa70-1c8dfb4570e7
 						- Horizontal
 						- Vertical
 						- Mixed
-					- different types of transparency
+					- different types of transparency #flashcard
-					  collapsed:: true
+					  id:: 648974ba-6db5-4d3a-af62-1695e7c3a9b7
 						- Distribution Transparency: The database feels as a single, logical entity
 						- Transaction Transparency: Ensures that all distributed transactions maintain distributed database’s integrity and consistency.
 						- Performance Transparency: must perform as if it were a centralized DBMS.
-					- advantages and disadvantages of distributed databases
+					- LATER advantages and disadvantages of distributed databases
 				- DONE XML
-				  collapsed:: true
+					- LATER XML definition and basic concepts #flashcard
-					- XML definition and basic concepts
+					  id:: 648974ba-afab-457e-9633-488450e9e16f
-					  collapsed:: true
 						- eXtensible Markup Language
 						- A meta-language (i.e. a language for describing other languages) that
 						  enables designers to create their own customised tags to provide
 						  functionality not available with HTML.
-					- Relational model versus XML
+					- LATER Relational model versus XML #flashcard
-					  collapsed:: true
+					  id:: 648974ba-d417-4eef-be28-46cd5894c5c7
 						- SQL
-						  collapsed:: true
 							- is a special-purpose programming language
 							- You can: manage data in a relational databases.
 						- XML
-						  collapsed:: true
 							- is a markup specification language
 							- You can: design ways of describing information (text or data), usually for storage, transmission, or processing by a program (you can use it in combination with a programming language).
 							- It says nothing about what you should do with the data (although your choice of element names may hint at what they are for).
-					- Well-formed XML, Valid XML
+					- LATER Well-formed XML, Valid XML #flashcard
-					  collapsed:: true
+					  id:: 648974ba-fb70-4207-8010-a8ddda35ccf7
 						- Adheres to basic structural requirements - Single root element
 						- Matched tags, proper nesting
 						- Unique attributes within elements
-					- DTD, XSD
+					- LATER DTD, XSD
-					  collapsed:: true
 						- DTD: Defines the valid syntax of an XML document
 						- XSD: a more comprehensive method of defining content model of
 						  an XML document.
+					- LATER Practice reading and writing XML, XSD
 				- DONE Data Mining
-				  collapsed:: true
+					- concept #flashcard
-					- concept
+					  id:: 648974ba-bf4c-4046-b7ce-510596ad421a
-					  collapsed:: true
 						- The process of extracting valid, previously unknown, comprehensible,
 						  and actionable information from large databases and using it to make
 						  crucial business decisions.
-					- different applications
+					- different applications #flashcard
-					  collapsed:: true
+					  id:: 648974ba-7440-4ac2-8730-b33e9f50570c
 						- Retail / Marketing
 						- Banking
 						- Insurance
 						- Medicine
 					- basic techniques
-					  collapsed:: true
+						- predictive modelling, #flashcard
-						- predictive modelling,
+						  id:: 648974ba-a007-420c-87db-1a029c1a39e6
-						  collapsed:: true
 							- uses observations to form a model of the important characteristics of some
 							  phenomenon
-						- database segmentation,
+						- database segmentation, #flashcard
-						  collapsed:: true
+						  id:: 648974ba-18a0-474e-96de-6a824969d0ec
 							- Uses unsupervised learning to discover homogeneous subpopulations in a database to improve the accuracy of the profiles.
-						- link analysis,
+						- link analysis, #flashcard
-						  collapsed:: true
+						  id:: 648974ba-0868-469f-9b8f-94a44163c87f
 							- Establishing links, called associations, between the individual
 							  records, or sets of records, in a database.
-						- deviation detection.
+						- deviation detection. #flashcard
-						  collapsed:: true
+						  id:: 648974ba-a77e-47ba-9f0d-6ed14e880333
 							- Identifies outliers, which express deviation from some previously
 							  known expectation and norm.
 				- DONE NoSQL
-				  collapsed:: true
+					- the motivation for NoSQL #flashcard
-					- the motivation for NoSQL
+					  id:: 648974ba-91af-424f-b392-928e947740de
-					  collapsed:: true
 						- By giving up ACID constraints, one can achieve
 						  much higher performance and scalability.
-					- explain the concepts of NoSQL
+					- explain the concepts of NoSQL #flashcard
-					  collapsed:: true
+					  id:: 648974ba-370b-44a8-9474-5b58d1d0dd28
 						- NoSQL databases (aka "not only SQL") are non-tabular databases and store
 						  data differently than relational tables. NoSQL databases come in a
 						  variety of types based on their data model. The main types are document,
 						  key-value, wide-column, and graph. They provide flexible schemas and
 						  scale easily with large amounts of data and high user loads.
-					- explain the application areas of NoSQL
+					- explain the application areas of NoSQL #flashcard
-					  collapsed:: true
+					  id:: 648974ba-b39b-47b7-8b9f-ca9250bef8ba
 						- NoSQL is an alternative, non-traditional DB technology to be
 						  used in large scale environments where (ACID) transactions are not a priority.
-						- CAP theorem:
+						- CAP theorem: #flashcard
-						  collapsed:: true
+						  id:: 648974ba-910d-42ae-89a9-5017194f6827
 							- There are 3 main properties for distributed management:
 							  1.  Consistency → A data item has the same value at the same time (to
 							      ensure coherency).