(using SQLite) DataGridView showing only three rows from my DB

Question

Hey there.. after days of trying to solve this problem by trying some variations of my code, I'm desperate. I'm trying to fill my DataGridView with SQLite database - it works.. but.. DatGridView shows me only a few rows , for whatever reason. additional info: SQLite queries work perfectly (tried in "DB Browser in SQLite") also tried UNION/UNION ALL and cmd.ExecuteReader/cmd.ExecuteNonQuery + cmd.ExecuteReader code: private void button1_Click( object sender, EventArgs e) { SQLiteConnection myconnection = new SQLiteConnection( "Data Source=C:\Users\jprochazka\Desktop\HG DB SQLite\hg_db07 - serverside\hg_db06\databaze_heinz_glas.db;Version=3" ); myconnection.Open(); SQLiteCommand cmd = new SQLiteCommand(); cmd.Connection = myconnection; cmd.CommandText = "SELECT id, nazev_tabulky, nazev_zarizeni, typ_zarizeni, vyrobce, umisteni, evidencni_cislo FROM Spotrebice UNION " + "SELECT id, nazev_tabulky, nazev_zarizeni, typ_zarizeni, vyrobce, umisteni, evidencni_cislo FROM Stroje UNION " + "SELECT id, nazev_tabulky, prurez, typ_kabelu, vyrobce, umisteni, evidencni_cislo FROM Prodluzovaci_Privody UNION " + "SELECT id, nazev_tabulky, nazev, oznaceni, vnejsi_vlivy, null, ev_c FROM Prostory UNION " + "SELECT id, nazev_tabulky, oznaceni, typ_zarizeni, vyrobce, umisteni, vyrobni_cislo FROM Rozvadece;" ; using (SQLiteDataReader sdr = cmd.ExecuteReader()) { DataTable dt = new DataTable(); dt.Load(sdr); sdr.Close(); myconnection.Close(); dataGridView1.DataSource = dt; } } Thanks for every advice.

Rajanikant Hawaldar · Answer

Is there any event is firing after row added to datagridview? if any event is firing then you have to check there. Did you try using SQLiteDataAdapter to bind datagrdiview

Zrnko Kávy · Answer

Number of columns are the same. Data types of each column are the same. The SQLite query works. There's propably a problem while loading into DataGridView

Zrnko Kávy · Answer

No events after loading. Pure DataGridView without any further changes. SQLiteDataAdapter works , thank you very much!

Sachin Singh · Answer

you need to join , unoin won't work here. Basic rules for combining two or more queries using UNION : 1.) number of columns and order of columns of all queries must be same. 2.) the data types of the columns on involving table in each query must be same or compatible. In your case all table have different number of columns and Names, so you need to join them, not union them. use proper joining key , i have just given an example string query=@" select * from Spotrebice sp join Stroje st on sp.Id=st.Spotrebice_Id join Prodluzovaci_Privody prp on prp.Id= st.Prodluzovaci_Privody join Prostory pro on pro.Id=prp.Prostory_Id join Rozvadece roz on roz.Id= pro.Rozvadece_Id "; cmd.Connection = myconnection; cmd.CommandText = query; using (SQLiteDataReader sdr = cmd.ExecuteReader()) { DataTable dt = new DataTable(); dt.Load(sdr); sdr.Close(); myconnection.Close(); dataGridView1.DataSource = dt; } }