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2 years ago

What is Join..?? Explain different types of joins.

Engineering

1 answer:

Anarel [89]2 years ago

5 0

Answer:

mainly used to combine two tables based on a specified common field between them. If we talk in terms of Relational algebra, it is the cartesian product of two tables followed by the selection operation. Thus, we can execute the product and selection process on two tables using a single join statement. We can use either 'on' or 'using' clause in MySQL to apply predicates to the join queries.

A Join can be broadly divided into two types:

Inner Join

Outer Join

Inner Join is a join that can be used to return all the values that have matching values in both the tables. Inner Join can be depicted using the below diagram.

The inner join can be further divided into the following types:

Equi Join

Natural Join

Now let us learn about these inner joins one-by-one.

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The drag force, Fd, imposed by the surrounding air on a

Ad libitum [116K]

Answer:

a) 23.551 hp

b) 516.89 hp

Explanation:

given:

$F_{d} =\frac{1}{2} C_{d} A_{p} V^{2} \\V_{a}=25 m/hr-->25*\frac{5280}{3600} =36.67ft/s\\V_{b}=70 m/hr-->70*\frac{5280}{3600} =102.67ft/s\\\\C_{d}=.28\\A=25 ft^2\\p=.075lb/ft^2$

required:

the power in hp

solution:

$(F_{d})_{a} =\frac{1}{2} C_{d} A_{p} V_{a} ^{2}$ .............(1)

by substituting in the equation (1)

=353.27 lbf

$(F_{d})_{b} =\frac{1}{2} C_{d} A_{p} V_{b} ^{2}$ ..........(2)

by substituting in the equation (2)

= 2769.29 lbf

power is defined by

P=F.V

$P_{a}=$ 353.27*36.67

=12954.411 lbf.ft/s

=12954.411*.001818

=23.551 hp

$P_{a}=$ 2769.29*102.67

= 284323 lbf.ft/s

= 284323*.001818

= 516.89 hp

3 0

2 years ago

Two balls are chosen randomly from an urn containing 8 white 4 black, and orange balls. Suppose that we win $ 2 for each black b

Scorpion4ik [409]

(-2,-10,-1,-2,-3,-4)

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2 years ago

What did the US and USSR agree on in the INF Treaty? They agreed to reduce nuclear weapons. They agreed that new European nation

faust18 [17]

Answer:

they agreed to reduce nuclear weapons

4 0

2 years ago

Read 2 more answers

If gas costs $3.50 per gallon, how much would it cost to drive 500 miles in a city in a car that is 58.3 km/L

Akimi4 [234]

1 liter = .264 gallon
1 km = .621 mile

this means that 58.3km/L is equal to 137.13mpg

so

500/137.13 = 3.65 gallons of gas

3.65 x 3.5 = $12.78

5 0

2 years ago

Is it possible to maintain a pressure of 10 kpa in a condenser that is being cooled by river water entering at 20 C.?

SIZIF [17.4K]

Answer:

Yes,If we use river water which is entering at 20⁰ C in the condenser then it is possible to maintain the pressure of 10 KPa in condenser.

Explanation:

Yes,If we use river water which is entering at 20⁰ C in the condenser then it is possible to maintain the pressure of 10 KPa in condenser.

The saturation temperature of steam is 45.81⁰ C at the pressure of 10 KPa which is higher than 20⁰C of river water. So river water at 20⁰C can be used to maintain the condenser pressure to 10 KPa.

7 0

2 years ago