How to select 4 tables in one sql query?

the four tables are nine, eight, seven, six the query i want to work is "SELECT DISTINCT tag FROM nine, eight, seven, six; ORDER BY date DESC" and it has to fit in one select command
Answer:

Some problems I see: You have given no indication via WHERE or JOIN clauses as to how the 4 tables are related - without those, you are simply going to get a (probably meaningless) Cartesian product of all rows from all the tables. You are only selecting column 'tag' - if it appears in only one of the tables, the others are unnecessary. Otherwise, you need to qualify from which table 'tag' is to be taken. You are ordering by 'date' which 1) is a poor choice for a column name (since it's also a data type in many DBMS) and 2) is not part of the selected columns (so ordering by it is meaningless)

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there should not be a semi-Colin. the same way you move to 'from' after calling the last desired field name you just leave a blank and move to the next keyword what is it you want from each table?

SELECT tag, date FROM nine union SELECT tag, date FROM eight union SELECT tag, date FROM seven union SELECT tag, date FROM six ORDER BY date DESC

Is your data setup so that each of those tables has a "tag" and "date" column? If not you will need to alias the the tables and use a combination of joins. If each table does have those columns you can use something like: select six.tag, seven.tag, eight.tag, nine.tag from six, seven, eight, nine order by six.date, seven.date, eight.date, nine.date desc

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