drop

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The drop
command removes the specified collection or view from the
federated database instance storage configuration. Use the wildcard "*"
to remove
all collections generated by the wildcard collection function (that is,
collectionName()
), including the wildcard collection rule itself.
You cannot individually remove collections generated by the wildcard
collection function.
Syntax
Parameters
Output
Examples
Drop Collections Examples
The following examples use the drop
command to remove sample
collections that were mapped to the sample dataset,
airbnb
and
weather,
in the AWS S3 store.
Basic Example
The following example uses the drop
command to remove a sample
collection named airbnb
in a database named sample
in the
storage configuration.
use sample db.runCommand({ "drop" : "airbnb"})
The previous command prints the following output:
{ "ok" : 1, "ns" : "sample.airbnb", "nIndexesWas" : 0 }
Wildcard Example
The following example uses the drop
command to remove the wildcard
collection function (collectionName()
) and all collections created
by the wildcard collection function in a database named sample
in
the storage configuration.
use sample db.runCommand ({ "drop" : "*" })
The previous command prints the following output:
{ "ok" : 1, "ns" : "sample.*", "nIndexesWas" : 0 }
Drop Views Example
The following command removes a view named "listings" on the airbnb
collection in the sample
database:
use sample db.runCommand({ "drop" : "listings" })
The previous command returns the following output:
Example
{ "ok" : 1, "ns" : "sample.listings", "nIndexesWas" : 0 }
Troubleshoot Errors
If the command fails, it returns one of the following errors.
Reason: Namespace (database, collection, or view) does not exist.
{ ok: 0, errmsg: "ns not found", code: 26, codeName: "NamespaceNotFound" }
Solution: Ensure that the namespace specified in the command is
valid and exists in the storage configuration. If necessary, use the
getStorageConfig
command to retrieve the list of valid databases,
collections, and views in the storage configuration.
Reason: Attempting to remove a collection created by the wildcard
collection function (collectionName()
).
{ ok: 0, errmsg: "cannot drop a collection created from a wildcard", code: 26, codeName: "NamespaceNotFound" }
Solution: Ensure that the collection you are dropping is not an
individual collection dynamically generated by the wildcard collection
function (collectionName()
). Data Federation does not support
dropping individual collections generated by the wildcard collection
function.