python - Duplicate inserts to Database Table -

my code works perfectly. scans text file , retrieves user defined information , stores access. issue i'm having is when code ran again, inserts data has been inserted.

is there easy way fix this? 1 thing data have in common have timestamp. possible use prevent duplicate?

cur.execute("select * main_setup order id"); rows = cur.fetchall() # outfilename = "out4.txt"  # regex pattern used extract timestamp file # search timestamps 2017-06-13-22.31.30.978293 dateregex_1 = r"[0-9]{4}-[0-9]{2}-[0-9]{2}-[0-9]{2}\.[0-9]{2}\.[0-9]{2}\.[0-9]+" dateregex_2 = r"[0-9]{4}-[0-9]{2}-[0-9]{2} \/ [0-9]+:[0-9]+:[0-9]+" # compile pattern regdexptrn_1 = re.compile(dateregex_1) regdexptrn_2 = re.compile(dateregex_2) field_names = ''   # call inserttoaccess function insert access database  cur.execute('select * lastran order id') tlran = cur.fetchall()  def insertlastran(jobname,timestamp):     print(jobname,timestamp)  def inserttoaccess(jobname, tableseq, timestamp, accesstablevalues, field_names):       # try:     params = (jobname, timestamp, tableseq, accesstablevalues[0], accesstablevalues[1], accesstablevalues[2],               accesstablevalues[3], accesstablevalues[4], \               accesstablevalues[5], accesstablevalues[6], accesstablevalues[7], accesstablevalues[8],               accesstablevalues[9], field_names)      cur.execute("insert report_table (job_name,run_ts,seq_num,field1,field2,field3,field4,field5,field6,field7,field8,field9,field10,field11) values \                     (?,?,?,?,?,?,?,?,?,?,?,?,?,?)", params);     conn.commit()     # except:     #    conn.rollback()   # extract current job fields def field_extract(filelines, fieldsarray, jobname, timestamp, delimit):     # empty string in append     # extracted fields     matchstr = ""     count = 0     tableseq = 0     accesstablevalues = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]     field_names = ''     line in filelines:         field in fieldsarray:             if field in line:                 key, value = line.split(delimit)                 matchstr += key.strip() + "\t\t : " + value.strip() + "\n"                 accesstablevalues[count] = value.strip()                 field_names += key.strip() + ';'                 count += 1                 if count == 10:                     tableseq += 1                     inserttoaccess(jobname, tableseq, timestamp, accesstablevalues, field_names)                     count = 0                     accesstablevalues = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]                     field_names = ''     if count > 0 , count < 10:         tableseq += 1         inserttoaccess(jobname, tableseq, timestamp, accesstablevalues, field_names)      # return string hold extracted fields     # each field onn separate line     return matchstr   # open input , output files test_file = open(r'c:\users\cqt7wny\desktop\new\savers_rept_dt0712.txt', 'r+') # outfile = open(outfilename, 'w')  # initialize used variables currentjobdata = [] startappending = false currentjobfound = false  # gaurav note fields_to_extract = [] outfilestr = "" line in test_file:     if startappending == false:         # jobstart in job_start:         if currentjobfound == false:             # find job name current report , exit loop    #====##########=====  gaurav note             rowx in rows:                 if rowx[1] in line:                     currentjobname = rowx[1]                     search_start_point = rowx[2]                     search_end_point = rowx[3]                     fields_to_extract = rowx[4].split(';')                     currentjobfound = true                     break             if currentjobname == 'xx':                 currentjobname = previousjobname                 search_start_point = previous_search_start_point                 search_end_point = previous_search_end_point                 fields_to_extract = previous_fields_to_extract          if search_start_point in line:             startappending = true      if startappending == true:         currentjobdata.append(line)      if len(search_end_point) > 1 , (search_end_point in line):         # job end found, stop gathering lines         startappending = false         # time stamp         # search in currnet line using         # compiled regex pattern         txt = "".join(currentjobdata)         # find occurance of timestamps on current job lines         timestamp = regdexptrn_1.findall(txt)         # check timestamp found         if len(timestamp) >= 1:             # if there more 1 timestamp in current             # job lines, first 1             timestamp = timestamp[0]         else:             timestamp = regdexptrn_2.findall(txt)             if len(timestamp) >= 1:                 timestamp = timestamp[0]                 # append found output output string         outfilestr += '########============ new job starts here ===========#########'         outfilestr += "\n"         outfilestr += "job# " + str(currentjobname)         outfilestr += "\n"         outfilestr += "timestamp: " + timestamp         outfilestr += "\n"          outfilestr = field_extract(currentjobdata, fields_to_extract, currentjobname, timestamp, ':')         insertlastran(currentjobname,timestamp)         print('current job name :', currentjobname, ' : ', timestamp)         print(outfilestr)         previousjobname = currentjobname         previous_search_start_point = search_start_point         previous_search_end_point = search_end_point         previous_fields_to_extract = fields_to_extract          currentjobname = 'xx'         currentjobfound = false          currentjobdata = []         fields_to_extract = []         search_start_point = ' '         search_end_point = ' '  test_file.close() 

there can different possible ways can prevent duplicate inserts .

1.check if data inserted/present in database/table.if not exists insert data else ignore/do not insert data .

2.you can create unique constraint on think duplicacy exist .

like alter table mytable add constraint constraint1 unique(column1)