# Mongo hack

## Update with using value inside doc

db.entities.updateOne(
    { entityId: 1553 },
    [{
        $set: {
            entities: [{
                orgnizationId: '$entity.organizationId',
                entityId: '$entity.entityId'
            }]
        }
    }]
])

### Results
<table>
<tr>
<td>Before</td>
<td>After</td>
</tr>
<tr>
<td>
<pre>
{
entityId: 1553
organizationId: 45
}
</pre>
</td>
<td>
<pre>
{
entityId: 1553
organizationId: 45
entities: [{
organizationId: 45
entityId: 1553,
}]
}
</pre>
</td>
</tr>
</table>

## Set in aggregation

db.rakeLiveChat_Users.aggregate([
    { $match: { rakeLiveChatUserId: 1553 } },
    {
        $lookup: {
            from: 'entities',
            localField: 'entityId',
            foreignField: 'entityId',
            as: 'entity'
        }
    },
    { $unwind: '$entity' },
    {
        $set: {
            entities: [{
                orgnizationId: '$entity.organizationId',
                entityId: '$entity.entityId'
            }]
        }
    }
])

### Results
<table>
<tr>
<td>Before</td>
<td>After</td>
</tr>
<tr>
<td>
<pre>
{
rakeLiveChatUserId: 1553,
entityId: 45
}
</pre>
</td>
<td>
<pre>
{
rakeLiveChatUserId: 1553,
entityId: 45,
entities: [{
organizationId: 4
entityId: 45,
}]
}
</pre>
</td>
</tr>
</table>

## Update fields if it not exists

db.entities.updateOne(
    { entityId: 808280 },
    [{
        $set: {
            lastName: {
                $switch: {
                    branches: [{ 
                      case: { $eq: [{ $type: "$lastName" }, 'missing'] }, 
                      then: 'lastName-3' 
                    }],
                    default: '$lastName'
                }
            },
            firstName: {
                $switch: {
                    branches: [{
                      case: { $eq: [{ $type: "$firstName" }, 'missing'] }, 
                      then: 'firstName-4'
                    }],
                    default: '$firstName'
                }
            }
        }
    }]
)

### Results
<table>
<tr>
<td>Before</td>
<td>After</td>
</tr>
<tr>
<td>
<pre>
{
entityId: 808280
firstName: 'firstName-1'
}
</pre>
</td>
<td>
<pre>
{
entityId: 808280
firstName: 'firstName-1',
lastName: 'lastName-3'
}
</pre>
</td>
</tr>
</table>