select count(distinct col1) + count(distinct case when col1 is null then 1 end) from YourTable.
Shouldn't select count(*) take more time to execute since it makes more operations? To output all the results from select * I need 4 minutes (not 32 seconds, as indicated by server log). I understand that the client has to output a lot of data and it will be slow, but what about the server's log?
SELECT CONCAT_WS(0x3A, user, password) FROM mysql.user WHERE user = 'root'-- (Privileged). Database Names.
Select (select count(*) from Table1) as Count1, (select count(*) from Table2) as Count2. Note: I tested this in SQL Server, so From Dual is not
1 1 1 NULL NULL NULL 2 2 NULL 1 3 1. Then. SELECT COUNT(*), COUNT(Field1), COUNT(Field2), COUNT(DISTINCT Field3) FROM Table1. Output Is: COUNT(*) = 4; -- count all rows, even null/duplicates --. Count only rows without null values on that field COUNT(Field1) = COUNT(Field2)...
Union select null, null, null, null, null, null, null from information_schema.tables. for a small database containing three tables. this instruction is used in sql injection I tried it and it worked but I didn't really know how it works can somebody help me...
(M): SELECT CONCAT(login, password) FROM members. 7. Строки без кавычек Есть несколько
Если вы используете базу данных MySQL, это очень важно, чтобы вы работали комфортно с командной строкой MySQL. На этом уроке мы расскажем, как использовать команду SELECT в MySQL с несколькими...
select count(value_x) People from table_a union select count(distinct value_x) People from table_b; We are currently getting: People 24998 23965. We have placed a break on report and computed a sum of count, but that's not really what we want. We would like to see just