import sqlite3
import time
import json
import pickle
import os
import random

REC_LIMIT = 100000

def getDBConn() -> sqlite3.Connection:
   conn = sqlite3.connect('test.db')
   # conn.execute('pragma journal_mode=memory')
   conn.execute('pragma journal_mode=WAL')
   conn.execute('pragma synchronous=NORMAL')
   #conn.execute('pragma mmap_size=268435456')
   conn.execute('pragma temp_store=MEMORY)
   # for row in conn.execute('pragma journal_mode').fetchall():
   #    print(row)
   # for row in conn.execute('pragma synchronous').fetchall():
   #    print(row)
   conn.commit()
   return conn

def initDB():
   with getDBConn() as conn:
      tbl_query = "CREATE TABLE IF NOT EXISTS test_table (eid INTEGER PRIMARY KEY, username TEXT, json TEXT, pickled_json BLOB)"
      conn.execute(tbl_query)

def genusername() -> str:
   arr = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9']
   result = []
   for i in range(30):
      result.append(random.choice(arr))
   return "".join(result)

def gen_records() -> list:
   records = []
   str_dummy_payload = '''json'''
   dummy_payload = json.loads(str_dummy_payload)
   dummy_payload = pickle.dumps(dummy_payload)
   for i in range(REC_LIMIT):
      records.append((genusername(), str_dummy_payload, dummy_payload))
   print("Generated records\n")
   return records


def cleanup():
   if os.access('test.db', os.F_OK):
      os.unlink('test.db')
   time.sleep(2)

def execute_many(records: list):
   cleanup()
   initDB()
   start = time.process_time()
   with getDBConn() as conn:
      cur = conn.cursor()
      cur.executemany("INSERT INTO test_table (username, json, pickled_json) VALUES (?, ?, ?)", records)
      cur.close()
   print(f"\nTime take while using executemany {time.process_time() - start}\n")


def single_insert(records: list):
   cleanup()
   initDB()
   start = time.process_time()
   with getDBConn() as conn:
      stmt = "INSERT INTO test_table (eid, username, json, pickled_json) VALUES (?,?,?,?);"
      for i,row in enumerate(records):
         row = (i,row[0],row[1],row[2])
         conn.execute(stmt, row)
      conn.commit()
   print(f"\nTime taken while using single insert {time.process_time() - start} \n")



def main():
   records = gen_records()
   single_insert(records)
main()




import sqlite3
import time

conn = sqlite3.connect('test.db')
cur = conn.cursor()
stmt = "SELECT * from test_table LIMIT 10;"
for i in range(1000000000):
    conn.execute(stmt)
    for row in cur.fetchall():
        # print(row)
        pass
cur.close()
conn.close()
print("Read Completed!")