All language subtitles for 1. AS

Till now we have learnt how to sort filter the data and how to limit the number of rows
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That we want to
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Retrieve
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Now
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The data that we have received, if you want to get different column name on that table
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The as keyword is used
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As will assign an alias to the column name or the table name
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Why it is used
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So sometimes you have written a complex function or you have added operators
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While retrieving the data
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Your column name will display all those things
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You want a meaningful name on the column
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When you have retrieved the data
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So that is why
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And as the word is used
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To provide the second name to that column or to that table
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What is the syntax for as
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It is select column name as
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the alias
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So you mention the
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Column name first
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And then you mention alias
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From table name
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You can also mention the table alias
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For example
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If you want to give your customer data to some other agency
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You would like to change the column headers
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Cust ID will not mean anything to the agency
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Single change cust ID to serial number
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Customer underscore name to name and age
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as Customer's age
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We'll write this query
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In the PG admin
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I am starting the as query now select
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Customer ID
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Customer ID as
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Serial number
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Since the word serial number has a space in between you need to use the double
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Quotation mark
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We need the customer name as name
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Since name does not have any space bar in between
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Will not put the
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Double quotation marks
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And age we need as the customer age
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From
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The table name which is customer
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Before running this
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Note that customer ID is written as
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The column customer ID is showing customer underscore ID
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Customer name is showing as customer underscore name and age is written as age
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Now, Let us run this
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you can see
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In the output
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The column name is serial number
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Name and customer_age
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Only the aliases
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that we provided are shown and not the original column name
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Providing aliases to column names is important when you are having Complex functions mentioned in the query
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Providing aliases to tables is important when you are using the joins
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We'll be discussing joins in the later part of the course when we understand the joins will also
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Revisit the as keyword there
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So in this lecture we learnt how to provide alias to columns
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In the next lecture we will learn about some aggregate functions
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Such as sum, count, average etc
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See you in the next video