can handle a larger data cache than the 32-bit version, so you'd optimize on physical I/O. Therefore, this may be an advantage if the amount of data cache is currently a bottleneck. There's no point in using 64-bit ASE with the same amount of "total memory" as for the 32-bit version, because 64-bit ASE comes with an additional overhead in memory usage -- so the net amount of data cache would actually be less for 64-bit than for 32-bit in this case. (Just for clarity: the 64-bit version is not twice as fast as the 32-bit version, and does not perform its I/O at double the size of the 32-bit version (I once heard someone state these as facts...)). Is it a good idea to use datarows locking for all tables by default ? Not by default; only if you're having concurrency (locking) problems on a table, and you're not locking many rows of a table in a single transaction, then you could consider datarows locking for that table. In all other cases, use either datapages or allpages locking. (I personally favor datapages locking as the default lock scheme for all tables because switching to datarows locking is fast and easy, whereas for allpages locking, the entire table has to be converted which may take long for large tables. Also, datapages locking has other advantages over allpages, such as not locking index pages, update statistics running at level 0, and the availability of the reorg command). What would you do when the ASE server's performance is bad ? "Bad performance" is not a very meaningful term, so you'll need to get a more objective diagnosis first. Find out (i) what such a complaint is based on (clearly increasing response times or just a "feeling" that it's slower?), (ii) for which applications/queries/users this seems to be happening, and (iii) whether it happens continuously or just incidentally. Without identifying the specific, reproducable problem, any action is no better than speculation. What do you do when a segment gets full ? Wrong: a segment can never get full (even though some error messages state something to that extent). A segment is a "label" for one or more database device fragments; the fragments to which that label has been mapped can get full, but the segments themselves cannot. (Well, OK, this is a bit of a trick question... when those device fragments full up, you either add more space, or clean up old/redundant data.)
Does the DBA candidate hold a Sybase Certification ? If (s)he has, consider that a plus !
Questions for a candidate DBA to ask your potential future employer
When you're being interviewed for a DBA vacancy, there are some things related to the DBA environment you might want to know as well. I'd suggest to check out at least the following:
Does the company have a Technical Support contract with Sybase ? A support contract is required for getting EBFs and for being able to ask questions about technical problems. Without a support contract, you're completely on your own; you should ask yourself if your can fulfill the company's expectations in that case. Which version of ASE are they using, and on which platform ? This matters: for example, if they appear to be running 11.0.3 on Data General, find out if they are aware that both this ASE version and this platform are no longer supported by Sybase. If they're not planning to upgrade to a supported version/platform soon, ask yourself if you want to be working there; you risk being on your own, without support, and with an out-of-date ASE version that stops you from keeping your ASE knowledge current.
How many servers, database and concurrent users do they have ? What's the database size like ? Is there a 24*7 uptime requirement ? It helps to know which scale you're talking about. If you're supposed to look after a 500 Gb, never-no-downtime, 3000-user system, check whether the salary you're being offered is of the same magnitude as the system. Is Sybase Replication Server involved ? If it is, and if you know RepServer, reconsider your financial demands -- upwards, that is. Reason is that RepServer DBAs are hard to find -- much harder than ASE DBAs. Are you also supposed to take care of their Oracle, MS-SQL, etc. servers ? Do you have to manage ASIQ or ASA (SQLAnywhere) as well ? You may want to know this in advance rather than find out on your first working day.... If you want to get a Sybase certification (or get a more recent one) will they pay for this ? It should make 'm happy that you're willing to get your certification, 'cos it will make you a better DBA; try to get them to pay for at least part of it. Tip: if you're talking to a management person, calling this a "win-win scenario" might help....
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