Search results
Results from the WOW.Com Content Network
In standard SQL:1999 hierarchical queries are implemented by way of recursive common table expressions (CTEs). Unlike Oracle's earlier connect-by clause, recursive CTEs were designed with fixpoint semantics from the beginning. [1] Recursive CTEs from the standard were relatively close to the existing implementation in IBM DB2 version 2. [1]
The SQL:1999 standard calls for a Boolean type, [1] but many commercial SQL servers (Oracle Database, IBM Db2) do not support it as a column type, variable type or allow it in the results set. Microsoft SQL Server is one of the few database systems that properly supports BOOLEAN values using its "BIT" data type [ citation needed ] .
HAVING and WHERE are often confused by beginners, but they serve different purposes. WHERE is taken into account at an earlier stage of a query execution, filtering the rows read from the tables.
Set operations in SQL is a type of operations which allow the results of multiple queries to be combined into a single result set. [1] Set operators in SQL include UNION, INTERSECT, and EXCEPT, which mathematically correspond to the concepts of union, intersection and set difference.
SQL-92 was the third revision of the SQL database query language. Unlike SQL-89, it was a major revision of the standard. Aside from a few minor incompatibilities, the SQL-89 standard is forward-compatible with SQL-92. The standard specification itself grew about five times compared to SQL-89.
Woof — it’s been a looooooong week. If you feel like you’ve been working like a dog, let us offer you the internet equivalent of a big pile of catnip: hilarious tweets about pets.
In the Faroe Islands, wild, unpredictable weather — fierce winds and rain, and thick fog that settles like a curtain — can sometimes make travel by car or ferry problematic.
Kneading (also known rather adorably as ‘making biscuits’) is a key sign of affection and is wonderfully relaxing for both cat and human — as long as you have a blanket over your lap that is ...