# How to ensure/drop indices?

PREREQUISITE

Ensure Indices

To ensure indices of a specific collection, run command collection ensureIndices <collectionName>
```
[Lottery] $ LotteryMongo/collection ensureIndices Lottery
```
To ensure indices of all collections defined inside a mongo module, run command collection ensureAllIndices
```
[Lottery] $ LotteryMongo/collection ensureAllIndices
```
To ensure indices of all collections in the project, run command ensureAllIndices
```
[Lottery] $ ensureAllIndices
```

Drop Indices

To drop indices of a specific collection, run command collection dropIndices <collectionName>
```
[Lottery] $ LotteryMongo/collection dropIndices Lottery
```
To ensure indices of all collections defined inside a mongo module, run command collection dropAllIndices
```
[Lottery] $ LotteryMongo/collection dropAllIndices
```
To drop indices of all collections in the project, run command dropAllIndices
```
[Lottery] $ dropAllIndices
```