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3 years ago

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

Engineering

1 answer:

Anarel [89]3 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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Answer:

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Explanation:

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3 years ago

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3 years ago

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3 years ago

A 30 mm thick AISI 1020 steel plate is sandwiched between two 10 mm thick 2024-T3 aluminum plates and compressed with a bolt and

denis-greek [22]

Answer:

275 MPa

Explanation:

Regardless of what it is holding, the stiffness of a bolt depends on its own material properties and geometry.

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$k = E * \frac{A}{l}$

I assume this one is made of steel, because regular bolts are steel.

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The longitude is given. (But note that in a real application you have to consider the length up to the nut.)

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3 years ago