Perbandingan Cross-product Dan Subset Query Pada Multiple Relasi Dengan Metode Cost-based

Ada beberapa model query yang digunakan untuk mengakses data pada 2 tabel atau lebih dalam basis data relasi. Dua model query yang umum antara lain adalah cross product dan subset query, dimana kedua model ini dapat menghasilkan data yang sama. Namun perlu diperhatikan cara mana yang lebih optimal sehingga pada akhirnya didapatkan query dengan waktu akses yang paling minimum. Dengan menggunakan basis data Oracle 10g Express Edition akan dilakukan penelitian untuk mencari model query yang lebih optimal dengan metode cost-based. Parameter yang akan dibandingkan adalah harga/biaya dan waktu yang dihasilkan pada perencanaan eksekusi. Penelitian dilakukan dengan pengelompokkan uji data seperti jumlah data, jumlah relasi, akses tabel penuh atau sebagian dan pengindeksan

Visualization of Information Based on Tweets From Meteorological, Climatological, and Geophysical Agency: BMKG

Indonesia is a country with high rate of natural disaster, so any information about early warning of natural disaster are very important. Social media such as Twitter become one of tools for spreading information about natural disaster warning from account of Meteorology, Climatology and Geophysics Agency (BMKG), therefore, the effectiveness of this kind of method for providing information have not known yet. The statement becomes the reason that the visualization is needed to analyze the information spread of natural disaster early warning with Twitter. This study is performed in 3 steps, which is retrieving, preprocessing then visualization. Retrieving process is used to get the tweet data of BMKG account in twitter then save into database, while preprocessing is done to process tweet data that has been saved in database by grouping the data according to the category, which includes Meteorology, Climatology, and Geophysics according to existing keyword, also reduce tweet data that is unimportant like BMKG's reply tweet toward other user's question. Visualization stage uses the result of preprocessing data into line chart graphic, bar chart and pie chart. Highest information spreading from BMKG tweet happened in Geophysics at March with 25987 re-tweets, while the highest peak happened at 2 March 2016 with information about 8.3 SR earthquake in Mentawai islands, West Sumatera with total of 6145 re-tweets