Page 7 - E-Modul Sistem Basis Data
P. 7
6.3.2 Indeks Sekunder (Secondary Index)............................................... 121
6.3.3 Struktur Penyimpanan (Storage Structure) .................................... 123
BAB 7. Bahasa Query ....................................................................................... 128
7.1 Bahasa Query Formal ........................................................................... 128
7.1.1 Operasi Seleksi (Select) ................................................................. 129
7.1.2 Operasi Projeksi (Project) .............................................................. 130
7.1.3 Operasi Cartesian Product ............................................................. 131
7.1.4 Operasi Union ................................................................................ 134
7.1.5 Operasi Set-Diference .................................................................... 135
7.1.6 Operasi Rename ............................................................................. 136
7.2 Bahasa Query Terapan ......................................................................... 140
7.2.1 Struktur Dasar ................................................................................ 142
7.2.2 Nilai Null ........................................................................................ 143
7.2.3 Manipulasi Data ............................................................................. 144
7.2.4 Data Definition Language .............................................................. 144
BAB 8. Pemrosesan Query ............................................................................... 147
8.1 Klasifikasi Aktivitas ............................................................................. 147
8.1.1 Estimasi (Perkiraan) Biaya Query .................................................. 148
8.1.1 Pengukuran Biaya Query ............................................................... 149
8.1 Operasi Seleksi ..................................................................................... 150
8.2.1 Algoritma Dasar ............................................................................. 150
8.2.2 Seleksi dengan Indeks .................................................................... 152
8.2.3 Seleksi dengan Pembandingan (Ketidaksamaan) .......................... 154
8.3 Operasi Join .......................................................................................... 156
8.3.1 Estimasi Ukuran Join ..................................................................... 157
8.4 Operasi Lain ......................................................................................... 159
vii
