Search results
Results from the WOW.Com Content Network
SQL provides the functions CEILING and FLOOR to round numerical values. (Popular vendor specific functions are TRUNC (Informix, DB2, PostgreSQL, Oracle and MySQL) and ROUND (Informix, SQLite, Sybase, Oracle, PostgreSQL, Microsoft SQL Server and Mimer SQL.)) Temporal (datetime) DATE: for date values (e.g. 2011-05-03). TIME: for time values (e.g ...
E. F. Codd mentioned nulls as a method of representing missing data in the relational model in a 1975 paper in the FDT Bulletin of ACM-SIGMOD.Codd's paper that is most commonly cited with the semantics of Null (as adopted in SQL) is his 1979 paper in the ACM Transactions on Database Systems, in which he also introduced his Relational Model/Tasmania, although much of the other proposals from ...
The valid time and transaction time do not have to be the same for a single fact. For example, consider a temporal database storing data about the 18th century. The valid time of these facts is somewhere between 1701 and 1800. The transaction time would show when the facts were inserted into the database (for example 1998-01-21).
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.
Date/Time (Extended): SQL Server's smalldatetime format has precision of 1 minute, minimum date value is 1900-01-01, maximum date value is 2079-06-06; datetime format has precision of 10/3 milliseconds (rounded to increments of .000, .003, or .007 seconds), minimum date value is 1753-01-01, maximum date value is 9999-12-31; datetime2 format has ...
Similar to MS SQL Server, it uses a BIT data type. [18] In Access it is known as a Yes/No data type [19] which can have two values; Yes (True) or No (False). The BIT data type in Access can also be represented numerically: True is −1 and False is 0. [20] This differs from MS SQL Server in two ways, even though both are Microsoft products:
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
Major DBMSs, including SQLite, [5] MySQL, [6] Oracle, [7] IBM Db2, [8] Microsoft SQL Server [9] and PostgreSQL [10] support prepared statements. Prepared statements are normally executed through a non-SQL binary protocol for efficiency and protection from SQL injection, but with some DBMSs such as MySQL prepared statements are also available using a SQL syntax for debugging purposes.