{"id":1335,"date":"2022-06-04T00:48:58","date_gmt":"2022-06-04T07:48:58","guid":{"rendered":"https:\/\/www.1keydata.com\/blog\/?p=1335"},"modified":"2022-06-04T00:48:59","modified_gmt":"2022-06-04T07:48:59","slug":"can-you-have-multiple-where-clauses-in-sql","status":"publish","type":"post","link":"https:\/\/www.1keydata.com\/blog\/can-you-have-multiple-where-clauses-in-sql.html","title":{"rendered":"Can You Have Multiple WHERE Clauses in SQL"},"content":{"rendered":"\n

Technically the answer is yes, it is possible to have multiple WHERE<\/strong> clauses in a SQL statement. For example, if you are using a subquery, you can certainly employ a WHERE<\/strong> clause within the subquery, and then again in the outer query. Another example is when you are combining two SQL statements with a UNION<\/strong> \/ UNION ALL<\/strong> \/ INTERSECT<\/strong> \/ MINUS<\/strong>. In this case, both SQL statements can have their own WHERE <\/strong>clause.<\/p>\n\n\n\n\n\n\n\n

However, notice in each of those cases there are also multiple SELECT<\/strong> statements as well, and each WHERE<\/strong> is associated with a single SELECT<\/strong>. In fact, in a SELECT<\/strong> statement, there can only be a single WHERE<\/strong> clause. This also applies to DELETE<\/strong> and UPDATE<\/strong> statements as well.<\/p>\n\n\n\n

Usually when people ask this question, though, the concern is not really whether it’s possible to have multiple WHERE<\/strong> clauses in a SQL statement, but whether it’s possible to specify multiple conditions in a SQL statement. The answer to this question is yes. You would do this using a single WHERE<\/strong> statement. Assuming there are two conditions and you want both of them to be true, you can use AND<\/strong> to connect the two conditions. If you want either one of them to be true, you can use OR<\/strong>.<\/p>\n\n\n\n

While it is possible to use a subquery with multiple WHERE<\/strong> clauses to specify multiple conditions,<\/p>\n\n\n\n

SELECT * FROM
(SELECT * FROM SALES_TABLE
WHERE REGION = 'EAST')
WHERE YEAR = 2021
-- This query has two WHERE clauses<\/code><\/p>\n\n\n\n

this is not an efficient query to use. A better way to achieve the same result is as follows:<\/p>\n\n\n\n

SELECT * FROM SALES_TABLE
WHERE REGION = 'EAST' and YEAR = 2021;<\/code><\/p>\n\n\n\n

<\/p>\n","protected":false},"excerpt":{"rendered":"

Technically the answer is yes, it is possible to have multiple WHERE clauses in a SQL statement. For example, if you are using a subquery, you can certainly employ a WHERE clause within the subquery, and then again in the outer query. Another example is when you are combining two SQL statements with a UNION […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[247],"tags":[],"_links":{"self":[{"href":"https:\/\/www.1keydata.com\/blog\/wp-json\/wp\/v2\/posts\/1335"}],"collection":[{"href":"https:\/\/www.1keydata.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.1keydata.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.1keydata.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.1keydata.com\/blog\/wp-json\/wp\/v2\/comments?post=1335"}],"version-history":[{"count":8,"href":"https:\/\/www.1keydata.com\/blog\/wp-json\/wp\/v2\/posts\/1335\/revisions"}],"predecessor-version":[{"id":1343,"href":"https:\/\/www.1keydata.com\/blog\/wp-json\/wp\/v2\/posts\/1335\/revisions\/1343"}],"wp:attachment":[{"href":"https:\/\/www.1keydata.com\/blog\/wp-json\/wp\/v2\/media?parent=1335"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.1keydata.com\/blog\/wp-json\/wp\/v2\/categories?post=1335"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.1keydata.com\/blog\/wp-json\/wp\/v2\/tags?post=1335"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}