what is difference between alter and update command?

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what is difference between alter and update command?

Alter command

Update command

1-Alter command belongs to DDL.

2-Alter command is used to modify existing table header.

Example-

i-Adding new column.

ii-Dropping Exiting column.

iii-Renaming the exiting column.

iv-Change the data type and size.

3-Alter command does not support where conditions.

1-Update command belong from DML.

2-Update command is used to modify the Existing table body.

 Example-

i-change the values.

ii-Rename exiting values.

 

3-Update commands supports where conditions.

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