Get most frequent value with SQL query -


i'm trying write sql query find value occurs frequently.

so far, have this:

select genre, count(*) frequency  booksread  group genre

this gives me output this: 

anthropological         1  biography               7  crime                   4  essay                   2

i want returned result 7. i've tried using top 1 java compiler doesn't seem it.

the ansi sql syntax be:

select genre, count(*) frequency booksread group genre order count(*) desc fetch first 1 row only;

not databases support syntax. many support limit:

select genre, count(*) frequency booksread group genre order count(*) desc limit 1;

however, exact syntax depends on database using.

you can use ansi standard window functions:

select * (select genre, count(*) frequency,              row_number() on (order count(*) desc) seqnum       booksread       group genre      ) g seqnum = 1;

if want ties use rank() instead of row_number().


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