Difference between revisions of "SQL Relational operators"
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==Purpose== | ==Purpose== | ||
Relational Operators | Relational Operators | ||
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|$||True if <expression1> is a sub string of <expression2>. Both <expression1> and <expression2>must be character strings. | |$||True if <expression1> is a sub string of <expression2>. Both <expression1> and <expression2>must be character strings. | ||
|- | |- | ||
| − | ||||True if <expression2> is a sub string of <expression1>. Both <expression1> and <expression2>must be character strings. | + | |<nowiki>|</nowiki>||True if <expression2> is a sub string of <expression1>. Both <expression1> and <expression2>must be character strings. |
|- | |- | ||
|==||True if <expression1> and <expression2> match, otherwise False. Both <expression1> and <expression2>must be character strings. The <expression2> can contain the wildcards below. | |==||True if <expression1> and <expression2> match, otherwise False. Both <expression1> and <expression2>must be character strings. The <expression2> can contain the wildcards below. | ||
|- | |- | ||
|} | |} | ||
| + | |||
Wildcards for == pattern matching: | Wildcards for == pattern matching: | ||
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{| class="wikitable" | {| class="wikitable" | ||
| − | !_||Any single character | + | !Operator||Description |
| + | |- | ||
| + | |_||Any single character | ||
|- | |- | ||
|%||Zero or more characters | |%||Zero or more characters | ||
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==Example== | ==Example== | ||
<code lang="recital"> | <code lang="recital"> | ||
| − | + | SELECT name, address, balance, cost*1.15; | |
| − | SELECT name, address, balance, cost*1.15 | + | FROM accounts; |
| − | FROM accounts | + | WHERE paid_date = date(); |
| − | WHERE paid_date = date() | + | ORDER BY name, paid_date |
| − | ORDER BY name, paid_date | + | |
| − | + | SELECT name, address, balance, cost*1.15; | |
| − | SELECT name, address, balance, cost*1.15 | + | FROM accounts; |
| − | FROM accounts | + | WHERE paid_date <= date(); |
| − | WHERE paid_date <= date() | + | ORDER BY name, paid_date |
| − | ORDER BY name, paid_date | + | |
| − | + | SELECT name, address, balance, cost*1.15; | |
| − | SELECT name, address, balance, cost*1.15 | + | FROM accounts; |
| − | FROM accounts | + | WHERE paid_date <> date(); |
| − | WHERE paid_date <> date() | + | ORDER BY name, paid_date |
| − | ORDER BY name, paid_date | + | |
| − | + | SELECT name, address, balance, cost*1.15; | |
| − | SELECT name, address, balance, cost*1.15 | + | FROM accounts; |
| − | FROM accounts | + | WHERE name == "%inc%"; |
| − | WHERE name == "%inc%" | + | ORDER BY name, paid_date |
| − | ORDER BY name, paid_date | + | |
| − | + | SELECT name, address, balance, cost*1.15; | |
| − | SELECT name, address, balance, cost*1.15 | + | FROM accounts; |
| − | FROM accounts | + | WHERE name | "inc"; |
| − | WHERE name | "inc" | + | ORDER BY name, paid_date |
| − | ORDER BY name, paid_date | + | |
| − | + | SELECT name, address, balance, cost*1.15; | |
| − | SELECT name, address, balance, cost*1.15 | + | FROM accounts; |
| − | FROM accounts | + | WHERE name $ "BigCo inc, BigCo plc"; |
| − | WHERE name $ "BigCo inc, BigCo plc" | + | ORDER BY name, paid_date |
| − | ORDER BY name, paid_date | + | |
</code> | </code> | ||
==Products== | ==Products== | ||
| − | Recital | + | Recital, Recital Server |
[[Category:Documentation]] | [[Category:Documentation]] | ||
| − | [[Category:SQL | + | [[Category:SQL|Operators,Relational]] |
| − | + | ||
Latest revision as of 15:50, 5 July 2011
Purpose
Relational Operators
Syntax
<expression1> operator <expression2>
See Also
INSERT, SQL OPERATORS, SELECT, UPDATE
Description
Relational Operators compare two expressions and evaluate to either True or False.
| Operator | Description |
|---|---|
| = | True if <expression1> and <expression2> are equal, otherwise False |
| < | True if <expression1> is less than <expression2>, otherwise False |
| <= | True if <expression1> is less than or equal to <expression2>, otherwise False |
| > | True if <expression1> is greater than the <expression2>, otherwise False |
| >= | True if <expression1> is greater than or equal to <expression2>, otherwise False |
| <> | True if <expression1> and <expression2> are not equal, otherwise False |
| != | True if <expression1> and <expression2> are not equal, otherwise False |
| # | True if <expression1> and <expression2> are not equal, otherwise False |
| $ | True if <expression1> is a sub string of <expression2>. Both <expression1> and <expression2>must be character strings. |
| | | True if <expression2> is a sub string of <expression1>. Both <expression1> and <expression2>must be character strings. |
| == | True if <expression1> and <expression2> match, otherwise False. Both <expression1> and <expression2>must be character strings. The <expression2> can contain the wildcards below. |
Wildcards for == pattern matching:
| Operator | Description |
|---|---|
| _ | Any single character |
| % | Zero or more characters |
Example
SELECT name, address, balance, cost*1.15; FROM accounts; WHERE paid_date = date(); ORDER BY name, paid_date SELECT name, address, balance, cost*1.15; FROM accounts; WHERE paid_date <= date(); ORDER BY name, paid_date SELECT name, address, balance, cost*1.15; FROM accounts; WHERE paid_date <> date(); ORDER BY name, paid_date SELECT name, address, balance, cost*1.15; FROM accounts; WHERE name == "%inc%"; ORDER BY name, paid_date SELECT name, address, balance, cost*1.15; FROM accounts; WHERE name | "inc"; ORDER BY name, paid_date SELECT name, address, balance, cost*1.15; FROM accounts; WHERE name $ "BigCo inc, BigCo plc"; ORDER BY name, paid_date
Products
Recital, Recital Server
