問題文
A value that governs how long the old images of rows are kept is set from the root for all the tenants at once, and it is back to the earlier value in one tenant after that tenant has been closed and opened. Which statement explains that?
選択肢
- The setting that was made from the root is written into the file of the root and no further, so a tenant reads a file that belongs to it at the close and takes up whatever value it happens to find in there.
- The setting that was made from the root reaches a tenant in memory alone, so it has to be made once more from inside the tenant if it is to outlast a close.
- The setting that was made from the root is taken over by a tenant for as long as the tenant has never set it, so this tenant had been holding a value of its own that came back into effect afterwards.
- The setting that was made from the root reaches a tenant both in memory and upon the disk, so it is the close itself that throws away the values a tenant is holding upon the disk.