You can also change from the default of using seconds to using days, hours or minutes by appending a d, h or m respectively.
The default is 6 hours, to compliment yum-updatesd running once an hour.
So that if the current metadata downloaded is less than this many seconds old then yum will not update the metadata against the repository.
While updating packages, yum will ensure that all dependencies are satisfied.
(See Specifying package names for more information) If the packages or globs specified match to packages which are not currently installed then update will not install them.
For supported Yum-based platforms (see Chapter 1, Installing My SQL on Linux Using the My SQL Yum Repository, for a list), you can perform an in-place upgrade for My SQL (that is, replacing the old version and then running the new version off the old data files) with the My SQL Yum repository.
As typical with new versions of shared libraries where there are differences or additions in symbol versioning between the newer and older libraries (for example, between the newer, standard 5.6 shared client libraries and some older—prior or variant—versions of the shared libraries shipped natively by the Linux distributions' software repositories, or from some other sources), any applications compiled using the updated, newer shared libraries will require those updated libraries on systems where the applications are deployed.
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