Questions tagged [terminology]

Clarification and disambiguation of terminology in order to focus on clear, consistent, distinct, and easily recognized usages for databases and database technology.

This tag is for discussing terminology with the goal of improving clarity in word usage in order to enhance consistent communication about topics related to databases.

This tag should be used infrequently and only when consensus is needed.

The terminology that we use for computer technology comes from many sources and some terms are used for a variety of different purposes. In many cases the context may be enough to avoid general confusion. However, some usages are ambiguous and would benefit from promoting a consensus.

Good Examples: For databases the terms tables, columns and rows are generally, but not universally, accepted.

Poor Examples: New acronyms, catch phrases, overused words, old acronyms, old usages, obsolete terms, et cetera.

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What is the difference between a connection and a session?

What is the difference between a connection and a session and how they are related?
jrara
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What is the difference between a "record" and a "row" in SQL Server?

There was a rather innocuous question about adding dates and times in SQL Server that set off a rather fascinating taxonomic debate. So how do we differentiate between these related terms and how we use them properly? Row Record
swasheck
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Commonly Used Acronyms by Database Administrators

What are the most commonly used acronyms among database administrators and what are their correlated meanings? This is for the community and those searching for meanings of commonly used terms and acronyms when working with databases, etc.
tacotuesday
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What does the word "SARGable" really mean?

SQL Server users use the term "sargable". I'm wondering if there is an objective implementation-agnostic timeless definition for "sargable." For instance, WHERE foo LIKE '%bar%' is said by many to be not sargable, but some RDBMSs are able to use…
Evan Carroll
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In SQL, is it composite or compound keys?

About SQL (Computing/Databases): When we have two or more fields in a table that, together, identify its records uniquely, what's the proper way of calling them? Composite or compound keys? I've seen on the web both uses so I'm not really sure.
igordcard
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Column vs Field: have I been using these terms incorrectly?

I feel kind of embarrassed here, I've always used the terms "column" and "field" completely interchangeably, which recently caused some confusion in a technical discussion. I was told, though, that this wasn't correct, that it should be…
BradC
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PostgreSQL: Immutable, Volatile, Stable

I'm unclear about the true meaning in the definitions for IMMUTABLE, VOLATILE and STABLE functions. I read the documentation, specifically the definitions of each. IMMUTABLE indicates that the function cannot modify the database and always…
Brooks
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Why the term "relation(al)"?

In english, we might talk about the relation between, say, Bob and Tim. Perhaps they're cousins. The term "relation" in this context makes sense to me. In the context of relational databases, I understand what the term refers to, but I don't…
Adam Zerner
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What does horizontal scaling mean?

In database context, I have come across horizontal scalability as one of the advantages of the NOSQL databases. What does the term mean? CouchDB on Wikipedia NoSQL on Wikipedia How would it compare to vertical scaling?
Lazer
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Why is COALESCE not a function?

The docs insist that ISNULL is a function, but COALESCE is not. Specifically, they say The ISNULL function and the COALESCE expression If I put on my Lisp hat, I can think of COALESCE as a macro and everything makes sense. However, I've never…
J. Mini
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Is there a generic term for tables and views?

I am looking for a generic term, e.g. for a database abstraction, that includes all tabular data structures like database tables, views, tabular query results aso. As far as I understand, 'entity' is not the proper term since this would correspond…
Pinke Helga
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What does "collation" mean?

I am learning sqlite from a book which has mentioned collation and collating sequence multiple times. What does it mean exactly in the database world?
mumtaz
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What exactly is the 'online' in OLAP and OLTP?

I'm a bit confused because I'm questioning the definition of 'online' in OLTP and OLAP. I used to think that 'online' here means that we want our answer in bounded time and based on the data available at an instance in time. But OLAP queries can…
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What is it called when you search the middle of a string instead of the beginning?

I am trying to polish up my vocabulary to better communicate with my fellow developers. We have several places in the site where we are debating if we should search for a string from the beginning 'running%' vs anywhere in the string '%running%. I…
danielson317
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Term for a one-row table?

Is there a specific term to describe a relation with a cardinality of one? I'm thinking particularly of RDBMS "special" one-row tables, for example, DUAL (Oracle), SYSIBM.SYSDUMMY1 (DB2, Derby) and RDB$DATABASE (Interbase, Firebird).
pilcrow
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