diff options
| -rw-r--r-- | README.md | 4 | ||||
| -rw-r--r-- | bucket.go | 1 | ||||
| -rw-r--r-- | cursor.go | 7 |
3 files changed, 12 insertions, 0 deletions
@@ -258,6 +258,10 @@ set to a key which is different than the key not existing. Use the `Bucket.Delete()` function to delete a key from the bucket. +Please note that values returned from `Get()` are only valid while the +transaction is open. If you need to use a value outside of the transaction +then you must use `copy()` to copy it to another byte slice. + ### Iterating over keys @@ -252,6 +252,7 @@ func (b *Bucket) DeleteBucket(key []byte) error { // Get retrieves the value for a key in the bucket. // Returns a nil value if the key does not exist or if the key is a nested bucket. +// The returned value is only valid for the life of the transaction. func (b *Bucket) Get(key []byte) []byte { k, v, flags := b.Cursor().seek(key) @@ -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) |