![]() ![]() Luckily, PDO has a dedicated function to get that single number right off the query, fetchColumn(). The following statement returns the first name, last name, and country of all customers. In case of the latter, only values of this field that are not null will be counted). Using SQLite ROWNUMBER() with ORDER BY clause example. Why is such results I'm not very good in SQL, maybe such behavior is expected It seems very strange and unlogical. The following example finds how many rows are in the stocktable: SELECT COUNT() FROM stock If the SELECT statement contains a GROUP BY clause, the COUNT ()function reflects the number of values in each group. But if i perform the query: SELECT, COUNT() FROM mytable I get only ONE row (with rightmost column is a correct count). the COUNT ()function returns the total number of rows in the table. (note that it doesn't matter which constant value to use as a count() function's parameter, be it *, 0 or 1 or anything - all works the same as long as it's a constant as opposed to the field name. I want to count how many rows are selected from query along with selected data. SELECT, 1 FROM mytable I get all records as expected with rightmost column holding '1' in all records. SELECT count (*) FROM goods WHERE category_id = 1 Instead, you should always ask your database to count the rows and then return the only number, with a query like this: SELECT count ( 1 ) FROM users The SQLite count () function can be used to return the number of rows in a result set. ![]() When you need to count rows that match some criteria in your database, under no circumstances you should select the actual rows and then use rowCount()! ![]()
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