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In this video, we will perform query operation in the same order table.

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You can see in here if you click the reset now this time I'm going to use Query Operation for that purpose.

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Click this query section.

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And as you can see that this time we will see both primary key and the sort key.

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So query operation is expecting and requiring us both primary k partition key and circuit.

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That means it is expecting to us the whole primary key.

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So in order to do that, I'm going to add the ID one.

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We can see that when we reset this one and click the run button, we have it two items.

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And if you click to query and give the partition key ID we need to give also sort key.

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So in the sort key, for example, I would like to give delivery.

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So if we can run this command, it is to turn us to the first item in the dynamic DB and we can perform

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quail patient successfully.

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As you can see that we have performed qualification both providing the partition and the third key.

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Also, we can add additional filter expressions in here like the scan operation, but this is the best

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practice if we have a sort key and would like to seek our table with the sort K, we should run the

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query operations.

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Scan operations are always costly and we should avoid to run second operations from our applications

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using the sort key index dynamo.

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DB Exactly knows where this records is using indexes in its database.

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It is using the consistent hashing storage run so it can quickly find out where data is and retrieve

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data very fast.

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So there is no lookup operation when querying with the keys on dynamic DB and this is the best practice

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to use to create a command with the sort key when querying your tables so we can also perform the filter

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expressions.

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If you expand this window, you can give, for example, total price.

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Is equal to 5000.

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And if you run query, you can see the exact same response.

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If you change the value of total price, you can see that there is no item is returned.

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So as you can see that we can also run query with the filter expressions.

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But the important thing is when performing query operation, you should always pass the primary partition

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key and the sort key.