ArangoDB: truncate: remove all the documents but keep indexes

‘truncate’ method is used to remove all the documents from a collection (it do not remove the indexes associated with the collection).

 

There are two ways to remove a collection.

a.   Using truncate method of collection

b.   Using truncate method of db

 

Using truncate method of collection

Syntax

collection.truncate()

 

Step 1: Let’s create a collection demodb by executing below statement.

db._create("demodb")

127.0.0.1:8529@demo> db._create("demodb")
[ArangoCollection 10954, "demodb" (type document, status loaded)]

127.0.0.1:8529@demo> db._collections()
[ 
  [ArangoCollection 10043, "_analyzers" (type document, status loaded)], 
  [ArangoCollection 10058, "_appbundles" (type document, status loaded)], 
  [ArangoCollection 10055, "_apps" (type document, status loaded)], 
  [ArangoCollection 10046, "_aqlfunctions" (type document, status loaded)], 
  [ArangoCollection 10067, "_fishbowl" (type document, status loaded)], 
  [ArangoCollection 10061, "_frontend" (type document, status loaded)], 
  [ArangoCollection 10040, "_graphs" (type document, status loaded)], 
  [ArangoCollection 10052, "_jobs" (type document, status loaded)], 
  [ArangoCollection 10064, "_modules" (type document, status loaded)], 
  [ArangoCollection 10049, "_queues" (type document, status loaded)], 
  [ArangoCollection 10954, "demodb" (type document, status loaded)] 
]

 

Step 2: Let’s add some content to demodb collection by executing below statements.

col = db.demodb

col.save({"id" : 1, "name" : "Krishna"})

 

Count number of elements in the collection using ‘count’ method.

col.count()

 

127.0.0.1:8529@demo> col = db.demodb
[ArangoCollection 10954, "demodb" (type document, status loaded)]

127.0.0.1:8529@demo> col.save({"id" : 1, "name" : "Krishna"})
{ 
  "_id" : "demodb/11019", 
  "_key" : "11019", 
  "_rev" : "_cRclYT2---" 
}

127.0.0.1:8529@demo> col.count()
1

  Truncate the collection elements and confirm the same using count method.

 

127.0.0.1:8529@demo> col.truncate()

127.0.0.1:8529@demo> col.count()
0

 

Using truncate method of db

Signature

db._truncate(collection-identifier)

db._truncate(collection-name)

 

Truncate a collection using id

Step 1: Create a collection with name test.

127.0.0.1:8529@demo> db._create("test")
[ArangoCollection 11517, "test" (type document, status loaded)]

127.0.0.1:8529@demo> db._collections()
[ 
  [ArangoCollection 10043, "_analyzers" (type document, status loaded)], 
  [ArangoCollection 10058, "_appbundles" (type document, status loaded)], 
  [ArangoCollection 10055, "_apps" (type document, status loaded)], 
  [ArangoCollection 10046, "_aqlfunctions" (type document, status loaded)], 
  [ArangoCollection 10067, "_fishbowl" (type document, status loaded)], 
  [ArangoCollection 10061, "_frontend" (type document, status loaded)], 
  [ArangoCollection 10040, "_graphs" (type document, status loaded)], 
  [ArangoCollection 10052, "_jobs" (type document, status loaded)], 
  [ArangoCollection 10064, "_modules" (type document, status loaded)], 
  [ArangoCollection 10049, "_queues" (type document, status loaded)], 
  [ArangoCollection 11517, "test" (type document, status loaded)] 
]

 

Step 2: Add some data to the test collection.

127.0.0.1:8529@demo> colId = db.test
[ArangoCollection 11517, "test" (type document, status loaded)]

127.0.0.1:8529@demo> colId.save({"id" : 1, "firstName": "Krishna"})
{ 
  "_id" : "test/11588", 
  "_key" : "11588", 
  "_rev" : "_cRczMnm---" 
}


127.0.0.1:8529@demo> colId.count()
1

 

Step 3: truncate the collection data using collection identifier.

127.0.0.1:8529@demo> db._truncate(colId)

127.0.0.1:8529@demo> colId.count()
0

 

Truncate a collection using collection name

Step 1: Add some data to the test collection.

127.0.0.1:8529@demo> colId = db.test
[ArangoCollection 11517, "test" (type document, status loaded)]

127.0.0.1:8529@demo> colId.save({"id": 123, "firstName" : "Sailu"})
{ 
  "_id" : "test/11683", 
  "_key" : "11683", 
  "_rev" : "_cRc1Yd----" 
}

127.0.0.1:8529@demo> colId.count()
1

 

Step 2: Truncate the contents of collection.

127.0.0.1:8529@demo> db._truncate("test")

127.0.0.1:8529@demo> colId.count()
0

 

 

 

 

 

 

 

 

 

Previous                                                    Next                                                    Home