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Insert Cards
An SQL INSERT statement adds one or more records to any single table in a relational database. Basic form Insert statements have the following form: The number of columns and values must be the same. If a column is not specified, the default value for the column is used. The values specified (or implied) by the statement must satisfy all the applicable constraints (such as primary keys, constraints, and constraints). If a syntax error occurs or if any constraints are violated, the new row is not added to the table and an error returned instead. Example: INSERT INTO phone_book (name, number) VALUES ('John Doe', '555-1212'); Shorthand may also be used, taking advantage of the order of the columns when the table was created. It is not required to specify all columns in the table since any other columns will take their default value or remain null: Example for inserting data into 2 columns in the phone_book table and ignoring any other columns which may be after the first ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Table (database)
In a database, a table is a collection of related data organized in Table (information), table format; consisting of Column (database), columns and row (database), rows. In relational databases, and flat file databases, a ''table'' is a set of data elements (values) using a model of vertical column (database), columns (identifiable by name) and horizontal row (database), rows, the cell (database), cell being the unit where a row and column intersect. A table has a specified number of columns, but can have any number of rows. Each row is identified by one or more values appearing in a particular column subset. A specific choice of columns which uniquely identify rows is called the primary key. "Table" is another term for relation (database), "relation"; although there is the difference in that a table is usually a multiset (bag) of rows where a relation is a set (computer science), set and does not allow duplicates. Besides the actual data rows, tables generally have associated wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Database Trigger
A database trigger is procedural code that is automatically executed in response to certain Event (computing), events on a particular Table (database), table or View (database), view in a database. The trigger is mostly used for maintaining the Database integrity, integrity of the information on the database. For example, when a new record (representing a new worker) is added to the employees table, new records should also be created in the tables of the taxes, vacations and salaries. Triggers can also be used to log historical data, for example to keep track of employees' previous salaries. Triggers in DBMS Below follows a series of descriptions of how some popular DBMS support triggers. Oracle In addition to triggers that fire (and execute PL/SQL code) when data is modified, Oracle Database, Oracle 10g supports triggers that fire when schema-level objects (that is, tables) are modified and when user logon or logoff events occur. Schema-level triggers * After Creation * Bef ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oracle Database
Oracle Database (commonly referred to as Oracle DBMS, Oracle Autonomous Database, or simply as Oracle) is a proprietary multi-model database management system produced and marketed by Oracle Corporation. It is a database commonly used for running online transaction processing (OLTP), data warehousing (DW) and mixed (OLTP & DW) database workloads. Oracle Database is available by several service providers on-premises, on-cloud, or as a hybrid cloud installation. It may be run on third party servers as well as on Oracle hardware ( Exadata on-premises, on Oracle Cloud or at Cloud at Customer). Oracle Database uses SQL for database updating and retrieval. History Larry Ellison and his two friends and former co-workers, Bob Miner and Ed Oates, started a consultancy called Software Development Laboratories (SDL) in 1977, later Oracle Corporation. SDL developed the original version of the Oracle software. The name ''Oracle'' comes from the code-name of a CIA-funded proj ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GUID
A Universally Unique Identifier (UUID) is a 128-bit label used to uniquely identify objects in computer systems. The term Globally Unique Identifier (GUID) is also used, mostly in Microsoft systems. When generated according to the standard methods, UUIDs are, for practical purposes, unique. Their uniqueness does not depend on a central registration authority or coordination between the parties generating them, unlike most other numbering schemes. While the probability that a UUID will be duplicated is not zero, it is generally considered close enough to zero to be negligible. Thus, anyone can create a UUID and use it to identify something with near certainty that the identifier does not duplicate one that has already been, or will be, created to identify something else. Information labeled with UUIDs by independent parties can therefore be later combined into a single database or transmitted on the same channel, with a negligible probability of duplication. Adoption of UUIDs is wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Z/OS
z/OS is a 64-bit operating system for IBM z/Architecture mainframes, introduced by IBM in October 2000. It derives from and is the successor to OS/390, which in turn was preceded by a string of MVS versions.Starting with the earliest: * OS/VS2 Release 2 through Release 3.8 * MVS/System Extensions (MVS/SE) * MVS/System Product (MVS/SP) Version 1 * MVS/System Product Version 2 (MVS/Extended Architecture, MVS/XA) * MVS/System Product Version 3 (MVS/Enterprise Systems Architecture, MVS/ESA) * MVS/ESA SP Version 4 * MVS/ESA SP Version 5 Like OS/390, z/OS combines a number of formerly separate, related products, some of which are still optional. z/OS has the attributes of modern operating systems but also retains much of the older functionality that originated in the 1960s and is still in regular use—z/OS is designed for backward compatibility. Major characteristics z/OS supportsSome, e.g., TSO/E, are bundled with z/OS, others, e.g., CICS, are separately priced. stable ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Select (SQL)
The SQL SELECT statement returns a result set of rows, from one or more tables. A SELECT statement retrieves zero or more rows from one or more database tables or database views. In most applications, SELECT is the most commonly used data manipulation language (DML) command. As SQL is a declarative programming language, SELECT queries specify a result set, but do not specify how to calculate it. The database translates the query into a " query plan" which may vary between executions, database versions and database software. This functionality is called the " query optimizer" as it is responsible for finding the best possible execution plan for the query, within applicable constraints. The SELECT statement has many optional clauses: * SELECT list is the list of columns or SQL expressions to be returned by the query. This is approximately the relational algebra projection operation. * AS optionally provides an alias for each column or expression in the SELECT list. Thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stored Procedure
A stored procedure (also termed prc, proc, storp, sproc, StoPro, StoredProc, StoreProc, sp, or SP) is a subroutine available to applications that access a relational database management system (RDBMS). Such procedures are stored in the database data dictionary. Uses for stored procedures include data-validation (integrated into the database) or access-control mechanisms. Furthermore, stored procedures can consolidate and centralize logic that was originally implemented in applications. To save time and memory, extensive or complex processing that requires execution of several SQL statements can be saved into stored procedures, and all applications call the procedures. One can use nested stored procedures by executing one stored procedure from within another. Stored procedures may return result sets, i.e., the results of a SELECT statement. Such result sets can be processed using cursors, by other stored procedures, by associating a result-set locator, or by applications. S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surrogate Key
A surrogate key (or synthetic key, pseudokey, entity identifier, factless key, or technical key) in a database is a unique identifier for either an ''entity'' in the modeled world or an ''object'' in the database. The surrogate key is ''not'' derived from application data, unlike a ''natural'' (or ''business'') key. Definition There are at least two definitions of a surrogate: ; Surrogate (1) – Hall, Owlett and Todd (1976): A surrogate represents an ''entity'' in the outside world. The surrogate is internally generated by the system but is nevertheless visible to the user or application. ; Surrogate (2) – Wieringa and De Jonge (1991): A surrogate represents an ''object'' in the database itself. The surrogate is internally generated by the system and is invisible to the user or application. The ''Surrogate (1)'' definition relates to a data model rather than a storage model and is used throughout this article. See Date (1998). An important distinction between a s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Database Schema
The database schema is the structure of a database described in a formal language supported typically by a relational database management system (RDBMS). The term "wikt:schema, schema" refers to the organization of data as a blueprint of how the database is constructed (divided into database tables in the case of relational databases). The formal definition of a database schema is a set of formulas (sentences) called integrity constraints imposed on a database. These integrity constraints ensure compatibility between parts of the schema. All constraints are expressible in the same language. A database can be considered a structure in realization of the database language. The states of a created conceptual schema are transformed into an explicit mapping, the database schema. This describes how real-world entities are Data modeling, modeled in the database. "A database schema specifies, based on the database administrator's knowledge of possible applications, the facts that can ent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Firebird (database Server)
Firebird and fire bird may refer to: Mythical birds * Phoenix (mythology), sacred firebird found in the mythologies of many cultures ** Fenghuang, sometimes called Chinese phoenix * Vermilion bird, one of the four symbols of the Chinese constellation representing fire * Bennu, Egyptian firebird * Huma bird, Persian firebird * Firebird (Slavic folklore) Automobiles * Pontiac Firebird, American pony car * General Motors Firebird, series of concept cars Aviation * AAM-A-1 Firebird, an American air-to-air missile of the 1940s * Chengdu J-10 (NATO reporting name: Firebird), a Chinese combat aircraft * Northrop Grumman Firebird, an American recon/surveillance aircraft * CargoLogicAir, a defunct British airline (callsign: FIREBIRD) Film and television * ''Firebird'' (film), a 2021 film directed by Peeter Rebane * ''The Firebird'' (1934 film), a murder mystery directed by William Dieterle * ''The Firebird'' (1952 film), a musical drama film directed by Hasse Ekman * "Fireb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DUAL Table
The DUAL table is a special one-row, one-column table present by default in Oracle and other database installations. In Oracle, the table has a single VARCHAR2(1) column called DUMMY that has a value of 'X'. It is suitable for use in selecting a pseudo column such as SYSDATE or USER. Example use Oracle's SQL syntax requires the FROM clause but some queries don't require any tables - DUAL can be used in these cases. SELECT 1+1 FROM dual; SELECT 1 FROM dual; SELECT USER FROM dual; SELECT SYSDATE FROM dual; SELECT * FROM dual; History Charles Weiss explains why he created DUAL: I created the DUAL table as an underlying object in the Oracle Data Dictionary. It was never meant to be seen itself, but instead used inside a view that was expected to be queried. The idea was that you could do a JOIN to the DUAL table and create two rows in the result for every one row in your table. Then, by using GROUP BY, the resulting join could be summarized to show the amount of sto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2003
2003 was designated by the United Nations as the International Year of Fresh water, Freshwater. In 2003, a Multi-National Force – Iraq, United States-led coalition 2003 invasion of Iraq, invaded Iraq, starting the Iraq War. Demographics The world population on January 1, 2003, was estimated to be 6.272 billion people and increased to 6.353 billion people by January 1, 2004. An estimated 134.0 million births and 52.5 million deaths took place in 2003. The average global life expectancy was 67.1 years, an increase of 0.3 years from 2002. The rate of child mortality was 6.85%, a decrease of 0.27Percentage point, pp from 2002. 25.54% of people were living in extreme poverty, a decrease of 1.31pp from 2002. There were approximately 10.6 million global refugees at the beginning of 2003, and the number was reduced to 9.7 million refugees by the end of the year. Afghanistan was the largest source of refugees, with a total of 2.1 million at th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
