Sql

Question 1

How do you eliminate duplicates in sql

Answer 1

Select distinct

Question 2

How do you name the column you are returning from database

Answer 2

As

Question 3

How do you select what table you are querying in the database

Answer 3

Select* if searching the entire database
Select from to specify a table

Question 4

String length

Answer 4

Len(column)
Length(column)

Question 5

How do you add conditions

Answer 5

Where

Question 6

How do you use the substring function

Answer 6

Substring(column,position of first character you want to return, total length of the substring)

Question 7

Dml

Answer 7

Data manipulation language

Question 8

Cast()

Answer 8

Can be used to convert anything from one data type to another.

Question 9

Coalesce

Answer 9

Coalesce(columna,columnb) if no value in a it returns value in b

Question 10

How do you change data types?

Answer 10

Cast
Cast as [data type]
From table

Question 11

How do you avoid failed returns when casting (error)

Answer 11

Safe_cast: returns null value where the errors are. This allows the action to be completed without failing the entire command.

Question 12

What data types are ther

Answer 12

Int
String
Datetime
Many more

Question 13

What is unix_date

Answer 13

UNIX_DATE returns the number of days that have passed since January 1, 1970 and is used to compare and work with dates across multiple time zones. You will likely use CAST most often.