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Retrieving data from a database and filtering results

I get the first 50 entries using this query. However, in the same table there is a flag with a name read, and I want to return only the first 50 records that are not read(i.e. isread=false). How can i achieve this? Can someone give me ideas for the requested request? I tried using subqueries.

SELECT * FROM notification WHERE toUserId = 'email' ORDER BY id DESC LIMIT 50;
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3 answers

Try to add a condition ANDto your suggestion of the WHERE: userID = 'email' AND flag = true. This will only return users with the true value for the flag, from which you can get the 50 best in their ultimate state.

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50 IsRead, , , Sql.

SELECT * FROM (SELECT TOP 50 * FROM notification) S WHERE toUserId = 'email' and isread=false

. MySql.

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SELECT * FROM notification WHERE toUserId = 'email' AND isread = 0 ORDER BY id DESC LIMIT 50;

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