Solution : https://service.sap.com/sap/support/notes/415073 (SAP Service marketplace login required)
Key words : 
~ftp//general/sapdb/ccms/note, basis support package sp42, basis support package sp62, prepare phase 'dynspcadd' terminates, prepare phase 'dynspcadd' takes, work process takes, executing exec sql, maxdb/sap db 7, p3ik049703 transport request, y4bk009441 transport request
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