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In SQL (Structured Query Language), the term cardinality refers to the uniqueness of data values contained in a particular column (attribute) of a database table. The lower the cardinality, the more duplicated elements in a column. Thus, a column with the lowest possible cardinality would have the same value for every row.
In a SQL database query, a correlated subquery (also known as a synchronized subquery) is a subquery (a query nested inside another query) that uses values from the outer query. This can have major impact on performance because the correlated subquery might get recomputed every time for each row of the outer query is processed.
Queries can be nested so that the results of one query can be used in another query via a relational operator or aggregation function. A nested query is also known as a subquery. While joins and other table operations provide computationally superior (i.e. faster) alternatives in many cases (all depending on implementation), the use of ...
In SQL, the unique keys have a UNIQUE constraint assigned to them in order to prevent duplicates (a duplicate entry is not valid in a unique column). Alternate keys may be used like the primary key when doing a single-table select or when filtering in a where clause, but are not typically used to join multiple tables.
Query by Example (QBE) is a database query language for relational databases. It was devised by Moshé M. Zloof at IBM Research during the mid-1970s, in parallel to the development of SQL . [ 1 ] It is the first graphical query language, using visual tables where the user would enter commands, example elements and conditions.
Native Queries, LINQ support, automatic schema evolution, Transparent Activation/Persistence, replication to RDBMS, Object Manager plugin for Visual Studio and Eclipse GemStone/S: 3.6.0 Smalltalk: None Objects and code Proprietary, free version available Persistent, transactional, multi-user Smalltalk developed by GemTalk Systems ...
Notice that "scriptName" is one of the pieces of the variable name. This is important to help make sure the variable is unique. Do not use let scriptNameSettingName = 'value here'; in the common.js file. If the user forgets the setting, you may get undeclared variable errors.
In some cases this is importing the exported functionality of a library, package or module but some mechanisms are simpler text file include operations. Import can be classified by level (module, package, class, procedure,...) and by syntax (directive name, attributes,...). File include