create(key='a', value={'k1': 'v1'}) >>> KV.get(KV.key == 'a').value {'k1': 'v1'} We can access specific parts of the JSON data using dictionary lookups: >>> KV.get(KV.value['k1'] == 'v1').key 'a' using the update() method: >>> KV.update(value=KV.value.update({'k1': 'v1-x', 'k2': 'v2'})).execute() 1 >>> KV.get(KV.key == 'a').value {'k1': 'v1-x', 'k2': 'v2'} We can also set individual parts of the the JSON data using the set() method: >>> KV.update(value=KV.value['k1'].set('v1')).execute() 1 >>> KV.get(KV.key == 'a').value {'k1': 'v1', 'k2': 'v2'} The set() method can also be used with objects,

create(key='a', value={'k1': 'v1'}) >>> KV.get(KV.key == 'a').value {'k1': 'v1'} We can access specific parts of the JSON data using dictionary lookups: >>> KV.get(KV.value['k1'] == 'v1').key 'a' using the update() method. Note that “k1=v1” is preserved: >>> KV.update(value=KV.value.update({'k2': 'v2', 'k3': 'v3'})).execute() 1 >>> KV.get(KV.key == 'a').value {'k1': 'v1', 'k2': 'v2', 'k3': 'v3'} update the value of “k1” and remove “k3” (“k2” will not be modified): >>> KV.update(value=KV.value.update({'k1': 'v1-x', 'k3': None})).execute() 1 >>> KV.get(KV.key == 'a').value {'k1': 'v1-x', 'k2': 'v2'}

# ('Post 3', []) insert(*pairs, **data) pairs – A flat list consisting of key, value pairs. E.g., k1 v1, k2, v2, k3, v3. The key may be a simple string or a JSONPath instance. data – keyword arguments .execute()) replace(*pairs, **data) pairs – A flat list consisting of key, value pairs. E.g., k1 v1, k2, v2, k3, v3. The key may be a simple string or a JSONPath instance. data – keyword arguments .execute()) set(*pairs, **data) pairs – A flat list consisting of key, value pairs. E.g., k1 v1, k2, v2, k3, v3. The key may be a simple string or a JSONPath instance. data – keyword arguments

# ('Post 3', []) insert(*pairs, **data) pairs – A flat list consisting of key, value pairs. E.g., k1 v1, k2, v2, k3, v3. The key may be a simple string or a JSON path. data – keyword arguments mapping .execute()) replace(*pairs, **data) pairs – A flat list consisting of key, value pairs. E.g., k1 v1, k2, v2, k3, v3. The key may be a simple string or a JSON path. data – keyword arguments mapping .execute()) set(*pairs, **data) pairs – A flat list consisting of key, value pairs. E.g., k1 v1, k2, v2, k3, v3. The key may be a simple string or a JSON path. data – keyword arguments mapping

# ('Post 3', []) insert(*pairs, **data) pairs – A flat list consisting of key, value pairs. E.g., k1 v1, k2, v2, k3, v3. The key may be a simple string or a JSONPath instance. data – keyword arguments .execute()) replace(*pairs, **data) pairs – A flat list consisting of key, value pairs. E.g., k1 v1, k2, v2, k3, v3. The key may be a simple string or a JSONPath instance. data – keyword arguments .execute()) set(*pairs, **data) pairs – A flat list consisting of key, value pairs. E.g., k1 v1, k2, v2, k3, v3. The key may be a simple string or a JSONPath instance. data – keyword arguments

name="chaincode1"> k1,1,v1), (k2,1,v2), (k3,1,v3), (k4,1,v4), (k5,1,v5) T1 -> Write(k1, v1'), Write(k2, v2') T2 -> Read(k1), Write(k3, v3') T3 -> Write(k2, v2'') T4 -> Write(k2 perform any read. Further, the tuple of keys k1 and k2 in the world state are updated to (k1,2,v1'), (k2,2,v2') 2. T2 fails validation because it reads a key, k1, which was modified by a preceding transaction

name="chaincode1"> k1,1,v1), (k2,1,v2), (k3,1,v3), (k4,1,v4), (k5,1,v5) T1 -> Write(k1, v1'), Write(k2, v2') T2 -> Read(k1), Write(k3, v3') T3 -> Write(k2, v2'') T4 -> Write(k2 perform any read. Further, the tuple of keys k1 and k2 in the world state are updated to (k1,2,v1'), (k2,2,v2') 2. T2 fails validation because it reads a key, k1, which was modified by a preceding transaction

name="chaincode1"> k1,1,v1), (k2,1,v2), (k3,1,v3), (k4,1,v4), (k5,1,v5) T1 -> Write(k1, v1'), Write(k2, v2') T2 -> Read(k1), Write(k3, v3') T3 -> Write(k2, v2'') T4 -> Write(k2 perform any read. Further, the tuple of keys k1 and k2 in the world state are updated to (k1,2,v1'), (k2,2,v2') 2. T2 fails validation because it reads a key, k1, which was modified by a preceding transaction

name="chaincode1"> performed by each of these transactions. World state: (k1,1,v1), (k2,1,v2), (k3,1,v3), (k4,1,v4), (k5,1,v5) T1 -> Write(k1, v1'), Write(k2, v2') T2 -> Read(k1), Write(k3, v3') T3 -> Write(k2, v2'') T4 -> Write(k2 perform any read. Further, the tuple of keys k1 and k2 in the world state are updated to (k1,2,v1'), (k2,2,v2') 2. T2 fails validation because it reads a key, k1, which was modified by a preceding transaction

name="chaincode1"> performed by each of these transactions. World state: (k1,1,v1), (k2,1,v2), (k3,1,v3), (k4,1,v4), (k5,1,v5) T1 -> Write(k1, v1'), Write(k2, v2') T2 -> Read(k1), Write(k3, v3') T3 -> Write(k2, v2'') T4 -> Write(k2 perform any read. Further, the tuple of keys k1 and k2 in the world state are updated to (k1,2,v1'), (k2,2,v2') 2. T2 fails validation because it reads a key, k1, which was modified by a preceding transaction