Špatný dotaz: Unknown column 'napsali' in 'where clause'
SELECT id,nazev,poradi,text,zkracene,url,id_kategorie,kod,datum,datum_zobrazovat FROM prispevek WHERE zobrazovat="A" AND (id_kategorie in(napsali-o-nas-do-druheho-pololeti-v-novych-ucebnach-a-laboratorich) or exists(select * from prispevek_kategorie pk where pk.id_prispevek = prispevek.id and pk.id_kategorie in (napsali-o-nas-do-druheho-pololeti-v-novych-ucebnach-a-laboratorich))) order by datum DESC ,id DESC