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| bio | website | |
|---|---|---|
| location | Munich | |
| age | ||
| visits | member for | 2 years |
| seen | 10 hours ago | |
| stats | profile views | 730 |
I'm looking for job as a software developer (Java) with focus on relational database technologies (Oracle, PostgreSQL)
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10h |
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Tools and methodologies to keep to DBs aligned We are quite satisfied using Liquibase for this. |
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1d |
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How to store many smallish time-series in a relational DB? I think this could be stored quite efficiently in Postgres using the hstore datatype ("NoSQL" like key/value type) or an array but that is obviously not an option. I think having one table for the values is probably going to be the most maintainable solution. You probably want to partition that table by measurement_id |
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2d |
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Inner join using an array column The equality operator in SQL is = not == |
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2d |
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Inner join using an array column The equality operator in SQL is = not == |
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May 19 |
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Make rows immutable allow Insert mysql5 Cross posted: stackoverflow.com/questions/16634741 |
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May 18 |
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How to make continues cluster? How can the table have 30 million rows in total yet have 20 million per month? Are only storing one and a half months in there? |
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May 18 |
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How to make continues cluster? Sounds more like a use case for partitioning rather than the cluster comand. |
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May 17 |
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Can't use SQL Server database on a networkpath Which DBMS are you using? Postgres? Oracle? Microsoft? ( SQL is just a query language, every RDBMS is a "SQL database") |
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May 16 |
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Is there a fast way to change column type without dropping the clustered index? How do you know it will improve performance? I doubt that you can really measure the difference. |
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May 16 |
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Performance Hit when upgrading to Oracle 11gr2 Seems to be, 11gR2 is twice as fast: it only needs half of the consistent gets. The number of physical reads simply means the data wasn't (yet) cached. What happened when you immediately ran the same statement again? |
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May 15 |
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Missing or lost transaction and no errors to show what went wrong As I have already commented: we had a similar situation. The server trace showed no sign of a rollback, delete or missing commit. Yet the rows weren't inserted. After changing the isolation level to serializable (nothing else was changed) this "vanishing" of rows never happened again. |
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May 15 |
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Missing or lost transaction and no errors to show what went wrong We had a similar issue with a SQL Server 2005 installation. We ran full trace on the server: no rollback no "hidden" deletes, the commits were there yet some rows simply weren't inserted. As far as we can tell, it went away when we changed the isolation level to serializable for the transaction in question. Didn't show up in the last 2 weeks - before the change it happened several times a day. I suspect the "new" READ_COMMITTED_SNAPSHOT mode to be the culprit, though I have no hard evidence for that. |
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May 15 |
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Configuring PostgreSQL for read performance Please show us the full table definition and all indexes together with the output of an explain analyze. More on posting this kind of questions: wiki.postgresql.org/wiki/Slow_Query_Questions |
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May 15 |
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Should I use two databases or two schemas? Why would you create a second Oracle instance (= database) just for a second application? Usually a new schema is absolutely enough. |
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May 15 |
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Looking for industry standard and/or tool to represent and export RDBMS metadata Just wanted to make sure. The answer does smell a little bit like it's spam. But if you are not related to the product it should be fine. |
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May 15 |
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Looking for industry standard and/or tool to represent and export RDBMS metadata Are you selling that product? |
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May 15 |
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How do I use subquery on the same table in MySQL? Are you sure that will work with MySQL? Last time I checked it didn't allow sub-queries on the same table for DELETE and UPDATE statements. Not sure if this includes co-related subqueries though. |
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May 15 |
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How do I use subquery on the same table in MySQL? In general you can use the same table in a sub-query. It's just that MySQL has a (stupid IMHO) restriction which prevents you of doing that in UPDATE or DELETE statements. |
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May 15 |
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Are all matching indexes (indices) searched for a query? @JackDouglas: You are probably thinking of index-only ("covering index") retrieval, right? In that case, you are right a index-only retrieval from a single column index is bound to faster. |
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May 14 |
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datetime vs timestamp in mysql 5.5 You do know the differences are documented in the manual? dev.mysql.com/doc/refman/5.5/en/datetime.html |
