35 lines
585 B
Markdown
35 lines
585 B
Markdown
# Project Notes - SQL Interlude - Chinook
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## Questions
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### How to use NOT in queries
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Why does
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```
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SELECT * FROM CUSTOMER
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WHERE COUNTRY NOT LIKE 'USA';
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```
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work and
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```
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SELECT * FROM CUSTOMER
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WHERE COUNTRY NOT 'USA';
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```
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does not work?
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### Answer
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To avoid using `LIKE` <br/>
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`WHERE NOT customer.country = "USA";` <br/>
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or <br/>
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`WHERE NOT != "USA";` <br/>
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are valid ways of forming the query.
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## Resources
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[How to concatenate columns in SQL - CONCAT_WS()](https://www.w3schools.com/sql/func_mysql_concat_ws.asp)
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## New Concepts/Syntax
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SQLite <br/>
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`strftime('%Y', InvoiceDate` |