Hot answers tagged terminology
ACID – Atomicity, Consistency, Isolation, Durability BASE - Basically Available, Soft-State, Eventually Consistent...essentially a counterpart to (though not really "opposite" of) ACID, this is the core principle of most NoSQL implementations. BI - Business Intelligence BLOB – Binary Large OBject CAP – Consistency, Availability, Partition tolerance... ...
To quote Joe Celko (not only can you find this reference all over the web and in his Wikipedia entry, but you will even see it on T-shirts at some conferences): Rows are not records. A lot of people point him out as a pedantic jerk who just likes to humble and verbally abuse newbies, and I will admit that is how he comes across. But I have also met him ...
Microsoft has in several places in their organization provided that the official name for tabular data storage per table-entry (to coin a taxonomic definition that serves my own purpose) is called a "ROW". I submit as evidence ROW_NUMBER, ROWCOUNT, ROWVERSION and the DataTable.Rows property, where a DataTable is a C# representation of a TSQL "table" object. ...
Both composite key and compound key describe a candidate key with more than one attribute. According to the Relational Database Dictionary (C.J.Date) they mean the same thing. In ER modelling the term "compound key" also has a more specific meaning. It means a key whose constituent attributes are references to keys in other entities - i.e. a compound key ...
I've just searched through the document "Information technology — Database languages — SQL Part 2: Foundation (SQL/Foundation)", which defines the ANSI standard for SQL as implemented by all major RDBMSes. The word row is used primarily throughout the document several hundred times, as expected. The word record was only used to describe a record that is ...
I'm still not sure why http://en.wikipedia.org/wiki/Compound_key was not consulted. It very clearly states (and is correct): In database design, a compound key is a key that consists of 2 or more attributes that uniquely identify an entity occurrence. Each attribute that makes up the compound key is a simple key in its own right. This is often ...
Horizontal Scaling Horizontal Scaling is essentially building out instead of up. You don't go and buy a bigger beefier server and move all of your load onto it, instead you buy 1+ additional servers and distribute your load across them. Horizontal scaling is used when you have the ability to run multiple instances on servers simultaneously. Typically it is ...
Singleton Table. In relational terms it is a relation with primary key ∅ (the empty set).
Relational database theory does not include the use of the word Field. Dr. E.F. Codd, who wrote the series of papers that provide the theoretical basis for RDBMS's never used the term. You can read his seminal 1970 paper A Relational Model of Data for Large Shared Data Banks if you want to check. Terms like Domain, Table, Attribute, Key and Tuple are ...
Because relational databases are rarely used in isolation, in order to avoid confusion between other parts of systems, I always refer to tables and rows and columns. In a client applications, we typically have other constructs, including datareaders, datasets, datarows, datatables, etc - for instance "field" is often used for on-screen data entry and Pascal ...
In Oracle terminology, it is an Index Organized Table, commonly referred to as an IOT. An index-organized table has a storage organization that is a variant of a primary B-tree. Unlike an ordinary (heap-organized) table whose data is stored as an unordered collection (heap), data for an index-organized table is stored in a B-tree index structure in a ...
Does "Heterogeneous" just refer to querying two different database engines in this context? Basically, yes. A "heterogeneous" query is executed on a "heterogeneous linked server". All queries to this linked server will be heterogeneous. And "heterogenous" is a subset of distributed queries Distributed data stored in multiple instances of SQL ...
The language keeps evolving. A few decades ago the literate people used "indices" instead of simpler "indexes". As we switched to "indexes", we eliminated an unnecessary complication and made the language more useful. The need to memorize a plural for "index" was pure overhead - it did not in any way help us communicate. Make no mistake, there used to be ...
Temporal Table or History Table are probably the terms you are looking for. Often you will see a nullable "end date" column in the table as well.
A junction table is a weak entity, but a weak entity may be a junction table. A junction table is not the same as a weak entity. A junction table is a type of weak entity. Tables used to resolve repeating groups are also weak entities. These are only junction tables if the repeating group contains a repeated foreign key relationship.
To the best of my knowledge yes. A problem that I see with your query is that you have no way to know what row is going to come back from your linked table. Is this just dummy code or is your query written this way?
ETL - Extract, Transform, Load
EAV - Entity-Attribute-Value (aka. the archenemy) UDF - User Defined Function SP - Stored Procedure
LAMP = Linux, Apache, MySQL and PHP
In any case, when one thing hasMany of another how/where does it show up in application and database logic? The only way I can think to answer this question is with another example of hasMany that may or may not answer your question. err, except I should have called the table "comment" but I think the point stands. I don't know that this really ...
A "candidate key" is any column or collection of columns that CAN uniquely identify a record in a table. A "primary key" is a candidate key that is defined as the primary key for the table. Internally, a primary key is simply a unique index, clustered or non-clustered, that is typically used in foreign key relationships. There is more to it than this, as ...
User terms surrogate key and natural key for primary key as a variant. Surrogate Key: Surrogate keys are keys that have no “business” meaning and are solely used to identify a record in the table. Such keys are either database generated (example: Identity in SQL Server, Sequence in Oracle, Sequence/Identity in DB2 UDB etc.) or system ...
Also QPS -- Queries Per Second
Yes it is. See Wikipedia
A securable is anything that can have permissions granted, denied, or revoked on in SQL Server. It's basically "something you can secure". Think about it like this: Your car is a securable. You would have to have been given keys (permissions) to access your car (securable). A securable is anything that can be accessible or inaccessible. Take a look at ...
TPS - Transactions per Second - measure database performance
Essentially the source table is the place where the data is coming from and the target table is the place where the data is going to or the table that an action is taking place on. They do not have to be in different schema's or have a different structure to each other and in fact they could actually be the same table.
A compound key would also define what you're describing. I've heard it called other things as well, like composite key. But note that the composite key is not the same as a compound key. Just trying to alert you to two vocabulary words.
IOT - Index Organized Table (Oracle) ACID - Atomicity, Consistency, Isolation, Durability CAP - Consistency, Availability, Partition tolerance... The three requirements of a distributed system (as they apply to a database) according to Eric Brewer's CAP Theorem. MV - Materialized View BLOB - Binary Large OBject CLOB - Character Large OBject DDL - Data ...
MDC - Multidimensional Clustering table MQT - Materialized Query Table (IBM DB2) UDT - User Defined Type
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