自己在做postgresql中作的正確的語法，SQL語句

原始表test_sql

1、查詢重複欄位的重複數select distinct (f1,f2,f3), count(*) from test_sql group by(f1,f2,f3)

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2、select distinct (f1,f2,f3), count(*) from test_sql group by(f1,f2,f3) having count(*) >1

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3、select distinct f1,f2,f3, count(*) from test_sql group by (f1,f2,f3)having count(*) >1 這樣報錯，由於有多個欄位distinct後加括號才能對

4、select (f1,f2,f3),min(id) from test_sql group by (f1,f2,f3) havingcount(*) >1 前面的(f1,f2,f3)是不能去括號的，也不能單獨查詢1個，因為group by (f1,f2,f3)，相當於把(f1,f2,f3)作為1個欄位了。

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5、select * from test_sql where id in (select min(id) from test_sqlgroup by (f1,f2,f3) having count(*) >1)

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6、select * from test_sql where id in (select min(id) from test_sqlgroup by (f1,f2,f3))

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7、delete from test_sql where id not in (select min(id) from test_sqlgroup by (f1,f2,f3))

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