I put the attribute "+1000 Attack Damage" on it (with Mc Edit) and I was not able to break any block with it in creative mode. I only tried it with a diamond sword so I don't know if this is the case with other items.
MC-25357
Block Breaking Issue
Resolved
Duplicate
0
Heinrich Müller
(Unassigned)
Unconfirmed
attribute, block
Minecraft 1.6.2
Retrieved
Working as intended duplicate of MC-18368
Swords do not break blocks in creative mode so that when you try to stab things and miss, you don't wreck your hard work.