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This list includes SQL reserved words – aka SQL reserved keywords, [1] [2] as the SQL:2023 specifies and some RDBMSs have added. ... USING SQL-2023: DB2: Mimer:
SQL allows the use of expressions in the select list to project data, ... The word NULL is a reserved keyword in SQL, used to identify the Null special marker ...
A query includes a list of columns to include in the final result, normally immediately following the SELECT keyword. An asterisk ("*") can be used to specify that the query should return all columns of all the queried tables. SELECT is the most complex statement in SQL, with optional keywords and clauses that include:
This category lists articles about SQL statements, clauses, and keywords. See also. List of SQL reserved words; Pages in category "SQL keywords"
SQL was initially developed at IBM by Donald D. Chamberlin and Raymond F. Boyce after learning about the relational model from Edgar F. Codd [12] in the early 1970s. [13] This version, initially called SEQUEL (Structured English Query Language), was designed to manipulate and retrieve data stored in IBM's original quasirelational database management system, System R, which a group at IBM San ...
Keywords for flow control in Transact-SQL include BEGIN and END, BREAK, CONTINUE, GOTO, IF and ELSE, RETURN, WAITFOR, and WHILE.. IF and ELSE allow conditional execution. This batch statement will print "It is the weekend" if the current date is a weekend day, or "It is a weekday" if the current date is a weekday.
Simple predicates use one of the operators =, <>, >, >=, <, <=, IN, BETWEEN, LIKE, IS NULL or IS NOT NULL. Predicates can be enclosed in parentheses if desired. The keywords AND and OR can be used to combine two predicates into a new one. If multiple combinations are applied, parentheses can be used to group combinations to indicate the order ...
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.