Read Data - Function in Where conditions

Hello, I try to add this Where Conditions in read data, without success.
id_tag = COALESCE({data:filtro_immagini},id_tag)
​
Where I wrong, I must to use another way?
​
Thank you for reply

Hi
​
What is COALESCE? Pure text? A javascript function? a php function? Are data:filtro_immagini and id_tag defined before you try this?
​
If data:filtro_immagini and id_tag defined before, you try to read database with id_tag='COALESCE('+value_f_data:filtro_immagini+','+value_of_id_tag+')'
For example, if data:filtro_immagini='abcd' and id_tag=12, you try to read records where id_tag = 'COALESCE(abcd,12)' like a pure string.

Hi ieaora,
​
Please try turning on the form Debugger - that should show you the MySQL query that is being created so that you can see where the error is.
​
Bob
​
PS for COALESCE see here

​
​

[read_immagini] => Array
        (
            [result] => Data not found!
            [log] => Array
                (
                    [0] => SELECT `Foto`.`cf_id` AS `Foto.cf_id`, `Foto`.`allegato` AS `Foto.allegato`, `Foto`.`g_id` AS `Foto.g_id`, `Foto`.`p_description` AS `Foto.p_description`, `Foto`.`id_tag` AS `Foto.id_tag`, `Foto`.`g_tag` AS `Foto.g_tag`, `Foto`.`p_cu` AS `Foto.p_cu`, `Foto`.`p_lotto` AS `Foto.p_lotto`, `Foto`.`id_listino` AS `Foto.id_listino`, `Foto`.`created` AS `Foto.created`, `Foto`.`modified` AS `Foto.modified`, `Foto`.`file_copertina` AS `Foto.file_copertina`, `Foto`.`p_tipo_galleria` AS `Foto.p_tipo_galleria`, `Foto`.`p_status_galleria` AS `Foto.p_status_galleria`, `Foto`.`g_solo_vetrina` AS `Foto.g_solo_vetrina`, `Foto`.`p_status` AS `Foto.p_status`, `Foto`.`p_tipo_formato` AS `Foto.p_tipo_formato`, `Foto`.`id_formati-off` AS `Foto.id_formati-off`, `Foto`.`p_id` AS `Foto.p_id`, `Foto`.`amazonaws_root` AS `Foto.amazonaws_root`, `Foto`.`p_exif_model_camera` AS `Foto.p_exif_model_camera`, `Foto`.`p_exif_copyright` AS `Foto.p_exif_copyright`, `Foto`.`p_exif_artist` AS `Foto.p_exif_artist`, `Foto`.`p_exif_datetime_scat` AS `Foto.p_exif_datetime_scat`, `Foto`.`p_exif_keywords` AS `Foto.p_exif_keywords`, `Foto`.`cestino` AS `Foto.cestino`, `Sottogalleria`.`id_sottogalleria` AS `Sottogalleria.id_sottogalleria`, `Sottogalleria`.`nome_sottogalleria` AS `Sottogalleria.nome_sottogalleria`, `Sottogalleria`.`sottogall_pub_priv` AS `Sottogalleria.sottogall_pub_priv`, `Sottogalleria`.`sottogall_passw` AS `Sottogalleria.sottogall_passw`, `Sottogalleria`.`sottogall_attiv_sosp` AS `Sottogalleria.sottogall_attiv_sosp`, `Sottogalleria`.`sottogall_solo_vetrina` AS `Sottogalleria.sottogall_solo_vetrina`, `Sottogalleria`.`sottogall_temp` AS `Sottogalleria.sottogall_temp`, `Sottogalleria`.`sottogall_data_inizio` AS `Sottogalleria.sottogall_data_inizio`, `Sottogalleria`.`sottogall_data_fine` AS `Sottogalleria.sottogall_data_fine`, `Sottogalleria`.`id_galleria` AS `Sottogalleria.id_galleria`, `Sottogalleria`.`id_listino` AS `Sottogalleria.id_listino`, `Sottogalleria`.`sottogall_data_ins` AS `Sottogalleria.sottogall_data_ins`, `Sottogalleria`.`timestamp` AS `Sottogalleria.timestamp`, `Sottogalleria`.`cestino` AS `Sottogalleria.cestino` FROM `xijhd_cf_product_data-2` AS `Foto` LEFT JOIN `xijhd_cf_sottogallerie` AS `Sottogalleria` ON `Foto`.`id_tag` = `Sottogalleria`.`id_sottogalleria` WHERE `Foto`.`cestino` = '0' AND `Foto`.`id_tag` = 'COALESCE(179,id_tag)' LIMIT 15;
                )

            [var] => false
        )

​
I tried also COALESCE({data:filtro_immagini},`Foto`.`id_tag`) without success.

Hi
​
1) read_immagini is an array. id_tag is a field of a Database Table. In MySQL, a table field can't be equal to an array.
​
2) What is COALESCE()?
​
3) What do you search?

Hi Colnem,
https://www.w3schools.com/sql/func_mysql_coalesce.asp
​
I want select all items if parameter is null.

OK I didn't know this SQL Function.
​
You can't compare in a Read Data Action a table field with the result of a SQL function. The operator == compare type and value.
​
I don't see how you set read_immagini. So I suppose that is the result of a Read Data action.
In read_immagini Read Data Action you have a section "Not found". So you can put a Read Data Action for all items in this section. So you read your records like you will if {data:read_immagini} is null.