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Diffstat (limited to 'cursor.go')
-rw-r--r--cursor.go7
1 files changed, 7 insertions, 0 deletions
diff --git a/cursor.go b/cursor.go
index 0d8ed16..006c548 100644
--- a/cursor.go
+++ b/cursor.go
@@ -10,6 +10,8 @@ import (
// Cursors see nested buckets with value == nil.
// Cursors can be obtained from a transaction and are valid as long as the transaction is open.
//
+// Keys and values returned from the cursor are only valid for the life of the transaction.
+//
// Changing data while traversing with a cursor may cause it to be invalidated
// and return unexpected keys and/or values. You must reposition your cursor
// after mutating data.
@@ -25,6 +27,7 @@ func (c *Cursor) Bucket() *Bucket {
// First moves the cursor to the first item in the bucket and returns its key and value.
// If the bucket is empty then a nil key and value are returned.
+// The returned key and value are only valid for the life of the transaction.
func (c *Cursor) First() (key []byte, value []byte) {
_assert(c.bucket.tx.db != nil, "tx closed")
c.stack = c.stack[:0]
@@ -41,6 +44,7 @@ func (c *Cursor) First() (key []byte, value []byte) {
// Last moves the cursor to the last item in the bucket and returns its key and value.
// If the bucket is empty then a nil key and value are returned.
+// The returned key and value are only valid for the life of the transaction.
func (c *Cursor) Last() (key []byte, value []byte) {
_assert(c.bucket.tx.db != nil, "tx closed")
c.stack = c.stack[:0]
@@ -58,6 +62,7 @@ func (c *Cursor) Last() (key []byte, value []byte) {
// Next moves the cursor to the next item in the bucket and returns its key and value.
// If the cursor is at the end of the bucket then a nil key and value are returned.
+// The returned key and value are only valid for the life of the transaction.
func (c *Cursor) Next() (key []byte, value []byte) {
_assert(c.bucket.tx.db != nil, "tx closed")
k, v, flags := c.next()
@@ -69,6 +74,7 @@ func (c *Cursor) Next() (key []byte, value []byte) {
// Prev moves the cursor to the previous item in the bucket and returns its key and value.
// If the cursor is at the beginning of the bucket then a nil key and value are returned.
+// The returned key and value are only valid for the life of the transaction.
func (c *Cursor) Prev() (key []byte, value []byte) {
_assert(c.bucket.tx.db != nil, "tx closed")
@@ -100,6 +106,7 @@ func (c *Cursor) Prev() (key []byte, value []byte) {
// Seek moves the cursor to a given key and returns it.
// If the key does not exist then the next key is used. If no keys
// follow, a nil key is returned.
+// The returned key and value are only valid for the life of the transaction.
func (c *Cursor) Seek(seek []byte) (key []byte, value []byte) {
k, v, flags := c.seek(seek)