This is personal study note
Copyright and original reference:
https://www.youtube.com/watch?v=hUXOf8JEupM&list=PLVsNizTWUw7HhYtI-4GGmlJ5yxNdwNI_X
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SQL statement: DML, DDL, DCL
DML: select, insert, update, delete
DDL: create, drop, alter
DCL: grand, revoke, deny
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3 values are inserted into 3 fields
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2 values are inserted into 2 fields (id, userName)
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Explicit order of field
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Auto_increment
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Get last id
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new start number for auto-incremented-id
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use "leap" for Auto_increment_id
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Copy large data and paste it into new table
Simpler statement without insert into
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update
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If price has been changed due to, for example, currency change,
you can use update statement without using where clause
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delete from
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Create large data tables for test
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remove table, time comparison
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BBK is duplicate in terms of PK
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ignore: if error occurs, that data is ignored
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