optimize cmd history

lib/db.py

@@ -72,9 +72,11 @@ def createFilterTable(file):
         print("db connection:",connection.total_changes)
 def addFineFilter(file,table,filterstr):
     with sqlite3.connect(file) as connection:
-        cmd = f"""INSERT INTO {table}(cmd) VALUES(?);"""
+        cmd_createFineFilter = f"""INSERT INTO {table}(cmd) VALUES(?);"""
+        cmd_checkIfExists = f"""SELECT * FROM {table} WHERE cmd = ?"""
         cursor = connection.cursor()
-        cursor.execute(cmd,(filterstr,))
+        if cursor.execute(cmd_checkIfExists,(filterstr,)).fetchone() == None:
+            cursor.execute(cmd_createFineFilter,(filterstr,))
 
 def writedb(jobs):
         with sqlite3.connect("../db/sqlite3.db") as connection: