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postgreSQL - in vs any

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I have tried both 1) smthng = any (select id from exmplTable) 2) smthng in (select id from exmplTable) and I am getting the same results for my data. Is there any difference for the two expresions ? No, in these variants are same: You can see - the execution plans are same too: postgres=# explain select * from foo1 where id in (select id from foo2); ┌──────────────────────────────────────────────────────────────────┐ │ QUERY PLAN │ ╞══════════════════════════════════════════════════════════════════╡ │ Hash Semi Join (cost=3.25..21.99 rows=100 width=4) │ │ Hash Cond: (foo1.id = foo2.id) │ │ ->

How do you use IN clauses with mysqli prepared statements [duplicate]

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This question already has an answer here: I have an array of integers, how do I use each one in a mysql query (in php)? 5 answers I’m moving some old code over to the new msqli interface using prepared statements, I’m having trouble with SQL statements containing the IN clause. I would just normally do this: $ids = '123,535,345,567,878' $sql = "SELECT * FROM table WHERE id IN ($ids)"; $res = mysql_query($sql); Converting this to mysqli and prepared statements I have tried a number of solutions: $ids = '123,535,345,567,878' $ids = implode($ids,','); $result = $msqli->prepare("SELECT foo,blar

Using 'IN' with a sub-query in SQL Statements

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Are there any performance issues of using "IN" keyword in SQL statements in places where we can use JOIN? SELECT xxx FROM xxx WHERE ID IN (SELECT Id FROM xxx) gbn No, it's OK to use. You can write the query above using IN, EXISTS in all RDBMS, some also support INTERSECT. Semantically this is a semi-join which "give me rows from table A where I have a at least one match in tableB". An INNER JOIN is "give me all matching rows" So if TableA has 3 rows and TableB has 5 rows that match: an INNER JOIN is 15 rows a semi-join is 3 rows This is why IN and EXISTS are pushed by me and the other SQL

How do you use IN clauses with mysqli prepared statements [duplicate]

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问题 This question already has an answer here: I have an array of integers, how do I use each one in a mysql query (in php)? 5 answers I’m moving some old code over to the new msqli interface using prepared statements, I’m having trouble with SQL statements containing the IN clause. I would just normally do this: $ids = '123,535,345,567,878' $sql = "SELECT * FROM table WHERE id IN ($ids)"; $res = mysql_query($sql); Converting this to mysqli and prepared statements I have tried a number of

IN vs ANY operator in PostgreSQL

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问题 What is the difference between IN and ANY operator in PostgreSQL? The working mechanism of both seems to be the same. Can anyone explain this with an example? 回答1: Logically , quoting the manual: IN is equivalent to = ANY . But there are two syntax variants of IN and two variants of the ANY construct. Details: How to use ANY instead of IN in a WHERE clause with Rails? The IN () variant taking a set is equivalent to = ANY() taking a set , as demonstrated here: postgreSQL - in vs any But the

PDO binding values for MySQL IN statement

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问题 I have an issue with PDO that I\'d really like to get an answer for after being plagued by it for quite some time. Take this example: I am binding an array of ID\'s to a PDO statement for use in a MySQL IN statement. The array would be say: $values = array(1,2,3,4,5,6,7,8); The database-safe variable would be $products = implode(\',\' $values); So, $products would then be a STRING with a value of: \'1,2,3,4,5,6,7,8\' The statement would look like: SELECT users.id FROM users JOIN products ON

ORDER BY the IN value list

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问题 I have a simple SQL query in PostgreSQL 8.3 that grabs a bunch of comments. I provide a sorted list of values to the IN construct in the WHERE clause: SELECT * FROM comments WHERE (comments.id IN (1,3,2,4)); This returns comments in an arbitrary order which in my happens to be ids like 1,2,3,4 . I want the resulting rows sorted like the list in the IN construct: (1,3,2,4) . How to achieve that? 回答1: You can do it quite easily with (introduced in PostgreSQL 8.2) VALUES (), (). Syntax will be

SQL Server IN vs. EXISTS Performance

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问题 I\'m curious which of the following below would be more efficient? I\'ve always been a bit cautious about using IN because I believe SQL Server turns the result set into a big IF statement. For a large result set, this could result in poor performance. For small result sets, I\'m not sure either is preferable. For large result sets, wouldn\'t EXISTS be more efficient? WHERE EXISTS (SELECT * FROM Base WHERE bx.BoxID = Base.BoxID AND [Rank] = 2) vs. WHERE bx.BoxID IN (SELECT BoxID FROM Base

Passing a varchar full of comma delimited values to a SQL Server IN function

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问题 Duplicate of Dynamic SQL Comma Delimited Value Query Parameterized Queries with Like and In I have a SQL Server Stored Procedure where I would like to pass a varchar full of comma delimited values to an IN function. For example: DECLARE @Ids varchar(50); SET @Ids = \'1,2,3,5,4,6,7,98,234\'; SELECT * FROM sometable WHERE tableid IN (@Ids); This does not work of course. I get the error: Conversion failed when converting the varchar value \'1,2,3,5,4,6,7,98,234\' to data type int. How can I

PDO binding values for MySQL IN statement

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I have an issue with PDO that I'd really like to get an answer for after being plagued by it for quite some time. Take this example: I am binding an array of ID's to a PDO statement for use in a MySQL IN statement. The array would be say: $values = array(1,2,3,4,5,6,7,8); The database-safe variable would be $products = implode(',' $values); So, $products would then be a STRING with a value of: '1,2,3,4,5,6,7,8' The statement would look like: SELECT users.id FROM users JOIN products ON products.user_id = users.id WHERE products IN (:products) Of course, $products would be bound to the statement