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[MUSIC]

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Let's remind ourselves of the CRUD
acronym and what we know so far.

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We know that to create a ruin database,
we use the keyword INSERT.

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For reading information, we use SELECT.

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But how about UPDATE?

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Unlike the other two it's not different
from the word used in the acronym.

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It's UPDATE.

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To write an UPDATE statement,
you'd write something like this.

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UPDATE, the table name,
a cue word we haven't used before

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SET because we want to set the value
of a column, next the column name,

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then the equal symbol and then the value.

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Now the equal sign in this case
is not doing the same thing

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as what it would do in
a condition in a WHERE clause.

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In the WHERE clause,
it's the equal to or equality operator.

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In the UPDATE statement,
it's know as an assignment operator.

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This is because we're
assigning a new value

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to an existing value
with a given column name.

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Let's see this in action.

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Let's first take a look
at the patrons table.

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Imagine we wanted to give a copy of this
database to an outsource developer and

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you wanted to anonymize any
sensitive data of your patrons

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while giving an accurate
representation of the user dataset.

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Let's use the template from before and
change all the last names to anonymous.

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The table name is patrons.

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The column name is last_name.

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And then the value of the text Anonymous.

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Let's execute the query.

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And it updates all the last
names in our table to Anonymous.

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But we still have zip codes and

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email addresses that could
be tracked back to somebody.

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Let's update both the email and
the zip_code.

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To do this, we can use a single statement
with each assignment separated like this.

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Let's write our statement now.

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Let's change the table to patrons.

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The first column is email.

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The second column is zip_code
with the relevant values.

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We've got the email as anon@email.com and
the zip codes set to five 5s.