email-database-code

email-database.py

@@ -0,0 +1,48 @@
+#This code is for making a database from given text File
+#In this sample code I've taken a text file to extract the emails and the number
+#of times they appear in text file.
+#Ex - From: abc.cdbh@gmail.com
+#index of email = 1
+
+
+import sqlite3
+
+conn = sqlite3.connect('emaildb.sqlite')
+cur = conn.cursor()
+
+cur.execute('DROP TABLE IF EXISTS Counts')
+
+cur.execute('''
+CREATE TABLE Counts (email TEXT, count INTEGER)''')
+
+fname = input('Enter file name: ')
+try:
+    fh = open(fname)
+except:
+    print('File cannot be opened:', fname)
+    exit()
+
+for line in fh:
+    if not line.startswith('From: '):
+        continue
+    pieces = line.split()
+    email = pieces[1] #give the index from the text file
+    cur.execute('SELECT count FROM Counts WHERE email = ? ', (email,))
+    row = cur.fetchone()
+    if row is None:
+        cur.execute('''INSERT INTO Counts (email, count)
+                VALUES (?, 1)''', (email,))
+    else:
+        cur.execute('UPDATE Counts SET count = count + 1 WHERE email = ?',
+                    (email,))
+    conn.commit()
+
+#printing required information
+#Here, they are sorted in DESC ORDER
+#and information is only asked for top 10 emails
+sqlstr = 'SELECT email, count FROM Counts ORDER BY count DESC LIMIT 10'
+
+for row in cur.execute(sqlstr):
+    print(str(row[0]), row[1])
+
+cur.close()