Database Administrators Stack Exchange
Database Administrators Stack Exchange

Questions tagged [database-agnostic]

Only use this tag when the question does not depend on a particular database management system.

No preference or requirements to answer for a particular database platform. Question may request a generic answer that covers multiple databases.

Per the question on allowing database-agnostic how to questions, a question that can be answered differently depending on the database management system (DBMS) should be asked in separate questions, one for each DBMS. This allows for a single correct answer. Sometimes the person asking may not realize that a question has different answers for different DBMSs. In these cases the question may need to be split or a DBMS-specific tag added and the database-agnostic tag removed.

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If a person's name is Null then how would it break the database?

I was reading this article on BBC. It tells a story of a person named Jenifer Null and how she faces day to day problems while using online databases like booking plane tickets, net banking etc. I am not well versed in databases and I do not use it…
Souradeep Nanda
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Arbitrarily ordering records in a table

A common need when using a database is to access records in order. For example, if I have a blog, I want to be able to reorder my blog posts in arbitrary order. These entries often have lots of relationships, so a relational database seems to make…
Tom Marthenal
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How to implement a 'default' flag that can only be set on a single row

For example, with a table similar to this: create table foo(bar int identity, chk char(1) check (chk in('Y', 'N'))); It doesn't matter if the flag is implemented as a char(1), a bit or whatever. I just want to be able to enforce the constraint that…
Jack Douglas
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Why won't some DBMS's allow rollback for certain DDL statements?

Recently I found out that MySQL doesn't support rollback of DDL such as "alter table"... Being used to PostgreSQL, that struck me as odd, but a friend of mine told me that even Oracle doesn't allow it.. Are there technical reasons for not supporting…
Joril
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Does any DBMS have a collation that is both case-sensitive and accent-insensitive?

Note this question is vendor/version agnostic It seems to me, as a speaker (typist, writer) of English, reasonable to expect words to be properly cased but not necessarily have the correct accents going in the right direction: as I mused in a…
onedaywhen
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What exactly is a database engine?

I have gone through the Wikipedia definition several times: A database engine (or "storage engine") is the underlying software component that a database management system (DBMS) uses to create, read, update and delete (CRUD) data from a…
Lazer
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Open Source Business Intelligence/DWH solutions

I wonder that this question hasn't already been asked. Google only has very few results for me that don't show a high quality tool What are some Open Source (also free is ok) solutions for Data Warehouses and more specifically Business Intelligence…
DrColossos
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Indexing from start or when performance problem arises?

My question is regarding use of indexes. Should I start indexing right from the start or when performance problem arises? We can also create temporary index while executing a query. What are the pros and cons of such techniques?
codecool
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Convert a date range to an interval description

A requirement in a recent project was to report when a resource would be fully consumed. As well as the exhaustion calendar date I was asked to show the remaining time in English-like format, something like "1 year, 3 months to go." The built-in…
Michael Green
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Which areas of a DBA's knowledge should a developer delve into?

I must admit the question is quite broad, so I'll try narrowing it down a bit. In our company we are 3-4 developers and have some SQL Server based installations running at our customer's sites (database sizes up to 100GB, up to 100 concurrent users,…
MicSim
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Multidimensional indices in databases

Which databases use real multidimensional indices? Is oracle ever using several indices to get data from tables, or will it always take the one that seems to have the highest selectivity? How about other dbms?
paweloque
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Do agile software development approaches apply to SQL?

I would like to learn if agile software development methods/principles/patterns are valid to SQL programming as well. If yes, where would be a good place to start learning about that? Are there any articles or books targeting agile development in…
Κύριε ἐλέησον
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Is there any security risk in having many foreign keys referencing a single table?

I have a teacher who told me that having a database with a table that's referenced by around 60% of the other tables was a security no-no. The problem is that he failed to explain why it was a security risk.
Cordelia_Chase
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Password hashes: Fixed-length binary fields or single string field?

I'm currently having am amusing debate with a friend, and we simply can't agree on the best method to store salted passwords in a database. The two options on the table are: Storing the hash and the salt together as a string, delimited by some…
TC Fox
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database DDLs and implicit commit

I've been taught that in RDBMS any DDL always causes an implicit commit, ending any active transaction at the time the DDL is issued. Now I found this page on the PostgreSQL wiki that states that PostgreSQL is able to perform DDL statements in a…
watery
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