Library cache lock brought by add trandata

After the morning meeting , A feedback from development , It is said that there is a perception exception in the service library at a certain time point

according to dba_hist_active_sess_history View to see if there are serious library cache lock

At that time , Excluding other businesses sql The impact , There is one alter table The operation of ogg by source

Unable to use 10046 Follow up , But we know that add trandata What is the general movement behind it , Roughly lock table, also alter table add supplemental Operation of the . There are generally three steps , There are two steps nowait Lock by , But if the watch is hot at this time , There is a step that will lead to ORA-00054 resource busy The error of .

combination ogg log, Let's confirm the relevant time points with each other

Good memory, such as bad pen , One fault, one idea .