новая тема

1 Relational DB design + FD + Normalization + keys + index + B-tree

Relational model stores data in tables (relations): rows = tuples, columns = attributes.
Key components: tables, attributes, tuples, constraints (PK/FK/UNIQUE/NOT NULL).
Mapping ER → relational: entity → table, 1:many → FK on many side, many:many → junction table, multivalued attribute → separate table.
Functional dependency (FD): X → Y means X uniquely determines Y (same X → same Y).
Armstrong axioms: reflexivity (if

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guduexam123

Q1 (b) How can you map a conceptual model to a relational model?

Mapping a conceptual (ER) model to a relational model is done by:

Converting entities into tables

Converting attributes into columns

Defining primary keys for each table

Representing relationships using foreign keys

Q1 (c) What is the use of DML in DBMS?

DML (Data Manipulation Language) is used to retrieve and manipulate data in database tables.
Examples: SELECT, INSERT, UPDATE, DELETE.

(d) List two reasons why we may choose to define

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dounia sva

Analys av När hundarna kommer av Jessica Schiefauer

I denna text ska jag analysera romanen ”När hundarna kommer” från 2015, skriven av Jessica Schiefauer. Boken handlar om Ester, en tonårstjej som bor i en liten stad, och hennes relationer till andra, bland annat hennes pojkvän Isak, familj och vänner. Parallellt får vi följa Anton, Isaks bror, som utvecklas mycket under berättelsens gång. Romanen tar upp flera viktiga teman, bland annat kärlek och beroende, våld och identitet. Och

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Physics

Chapter -1

electric field:-the sphere arround a source change in which a test charge would experience a force is called electric field.

Electric field lines: An electric field is represented by same emajinary lines of force which are called electric field.

properties:-1)they are emajinary lines of force.

2)in case of positive source change they are readily directed outward.

3) they are not closed line.

mathematically define of electric field:-  the electric force per unit test charge is called

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Ammedment

1. Right to Equality (Articles 14–18)

This right ensures equality before law and equal protection of laws to all persons. It prohibits discrimination on grounds of religion, race, caste, sex or place of birth. It also abolishes untouchability and titles.

Limitations:

Equality does not mean absolute equality. The State can make reasonable classification and special provisions for women, children, Scheduled Castes, Scheduled Tribes and Other Backward Classes.

2. Right to Freedom (Articles 19–22)...

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science

Chemical Reaction

A chemical reaction is a process in which one or more substances, known as reactants, undergo a transformation to form new substances with different chemical properties, known as products. During a chemical reaction, the arrangement of atoms in the reactants changes, leading to the creation of new bonds and the breaking of old ones. Chemical reactions are fundamental to understanding how matter interacts and changes in the world around us.

For example, hydrogen gas combines with

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pharm exam 1

Important drug terms to know:

1. Onset: Time it takes for the drug to reach the minimum effective concentration

2. Peak drug level: highest drug concentration in the blood

3. Trough drug level: lowest concentration before next dose

4. Duration: Length of time the drug exerts a therapeutic effect

5. Side effects: Secondary drug effects

6. Adverse reactions: Unintentional or unexpected reactions

7. Drug interactions: Changed action of the drug as a result of interaction with another drug

8. Drug

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prevodioci

Vrste programskih prevodioca?Asembleri,Makroprocesori,prevodioci jezika viseg nivoa,hibridni prevodioci,multijezicki prevodioci.Sta su asembleri? Asembleri su programski prevodioci koji se koriste za prevodjenje zapisa sa nivoa asemblerskog jezika na nivo masinskog jezika.Sta su makroprocesori i sastavni delovi?Makroprocesori su programski prevodioci koje se koriste za prevodjenje makroasemblerske naredbe u niz asemblerskih naredbi.Osnovni delovi su makroprocesor i asembler.Navesti razliku izmedju

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ddddd

Stats vs eventstats vs streamstats: stats collapses events, aggregates only; eventstats keeps events for per-event comparison; streamstats is rolling/windowed and order-sensitive. Chart vs timechart: chart groups non-time data using over/by; use fillnull to handle gaps. timechart bins _time automatically; set interval with "span=12h". Remember, "chart count over X by Y""chart count by X,Y" in grouping.

Eval: "tostring(field, "duration")" formats numeric time; "case()" handles multi-condition

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