Operator Description Less than Greater than Less than or equal to Greater than or equal to Equal Not equal Not equal (non-standard but popular syntax) The The statement shown above is equivalent to the following statement: SELECT 3 >= 2 AND 3 <= 6; To
test if a value does not fall within the specified range use SELECT 3 NOT BETWEEN 2 AND 6; The statement shown above is equivalent to the following statement: The presence of NULL in a SELECT NULL BETWEEN 2 AND 4; -- null SELECT 2 BETWEEN NULL AND 6; -- null The SELECT 'Paul' BETWEEN 'John' AND 'Ringo'; -- true Note that the value, min, and max parameters to IS NULL and IS NOT NULL#The Using select NULL IS NULL; -- true But any other constant does not: SELECT 3.0 IS NULL; -- false IS DISTINCT FROM and IS NOT DISTINCT FROM#In SQL a SELECT NULL IS DISTINCT FROM NULL; -- false SELECT NULL IS NOT DISTINCT FROM NULL; -- true In the example shown above, a The following truth table demonstrate the handling of
GREATEST and LEAST#These functions are not in the SQL standard, but are a common extension. Like most other functions in Presto, they return null if any argument is null. Note that in some other databases, such as PostgreSQL, they only return null if all arguments are null. The following types are supported: Returns the largest of the provided values. least(value1, value2, ..., valueN) → [same as input]#Returns the smallest of the provided values. Quantified Comparison Predicates: ALL, ANY and SOME#The expression operator quantifier ( subquery ) For example: SELECT 'hello' = ANY (VALUES 'hello', 'world'); -- true SELECT 21 < ALL (VALUES 19, 20, 21); -- false SELECT 42 >= SOME (SELECT 41 UNION ALL SELECT 42 UNION ALL SELECT 43); -- true Here are the meanings of some quantifier and comparison operator combinations:
LIKE#The LIKE operator is used to match a specified character pattern in a string. Patterns can contain regular characters as well as wildcards. Wildcard characters can be escaped using the single character specified for the ESCAPE parameter. Matching is case sensitive. Syntax: expression LIKE pattern [ ESCAPE 'escape_character' ] if
Examples: SELECT * FROM (VALUES ('abc'), ('bcd'), ('cde')) AS t (name) WHERE name LIKE '%b%' --returns 'abc' and 'bcd' SELECT * FROM (VALUES ('abc'), ('bcd'), ('cde')) AS t (name) WHERE name LIKE '_b%' --returns 'abc' SELECT * FROM (VALUES ('abc'), ('bcd'), ('cde')) AS t (name) WHERE name LIKE 'b%' --returns 'bcd' SELECT * FROM (VALUES ('abc'), ('bcd'), ('cde')) AS t (name) WHERE name LIKE 'B%' --returns nothing SELECT * FROM (VALUES ('a_c'), ('_cd'), ('cde')) AS t (name) WHERE name LIKE '%#_%' ESCAPE '#' --returns 'a_c' and '_cd' SELECT * FROM (VALUES ('a%c'), ('%cd'), ('cde')) AS t (name) WHERE name LIKE '%#%%' ESCAPE '#' --returns 'a%c' and '%cd' Which comparison operators can you use in a logical expression related to the WHERE clause of the select statement there are 3 correct answers to this question?Answer: The SELECT statement uses the IS NOT NULL and less than (<) comparison operators in the WHERE clause.
Which comparison operators can you use in a WHERE clause?One way to restrict the data presented from a query is to use a WHERE clause. WHERE is used to return data that matches a specified condition and is combined with the comparison operators = , != , > , < , >= , and <= .
Which types of logical comparisons are used in WHERE clause?The SQL WHERE clause is used to restrict the number of rows affected by a SELECT, UPDATE or DELETE query. The WHERE condition in SQL can be used in conjunction with logical operators such as AND and OR, comparison operators such as ,= etc.
Can we use comparison operator with WHERE clause in SQL?In SQL, comparison operators are always used in the WHERE clause with the SELECT, UPDATE, and DELETE statements.
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