In [1]:

    

import sqlite3
conn = sqlite3.connect('pmcv2-full.db')
c = conn.cursor()
#create tables
c.execute('''CREATE TABLE refs (pmid integer, refpmid integer)''')
c.execute('''CREATE TABLE pmcidmap (pmid integer, pmcid integer)''')
c.execute('''CREATE TABLE meta (pmid integer, title text, journal_id text, pubdate date)''')
c.execute('''CREATE TABLE authors (pmid integer, authnum integer, fn text, ln text, afil text)''')
c.execute('''CREATE TABLE keywords (pmid integer, keyword text)''')
c.execute('''CREATE TABLE abstracts (pmid integer, abstract text)''')
#merge file 1
c.execute('''ATTACH DATABASE 'pmcv2-AB.db' AS 'extdb' ''')
c.execute('''INSERT INTO main.refs SELECT * FROM extdb.refs''')
c.execute('''INSERT INTO main.pmcidmap SELECT * FROM extdb.pmcidmap''')
c.execute('''INSERT INTO main.meta SELECT * FROM extdb.meta''')
c.execute('''INSERT INTO main.authors SELECT * FROM extdb.authors''')
c.execute('''INSERT INTO main.keywords SELECT * FROM extdb.keywords''')
c.execute('''INSERT INTO main.abstracts SELECT * FROM extdb.abstracts''')
c.execute('''DETACH DATABASE 'extdb' ''')

#merge file 2
c.execute('''ATTACH DATABASE 'pmcv2-CH.db' AS 'extdb' ''')
c.execute('''INSERT INTO main.refs SELECT * FROM extdb.refs''')
c.execute('''INSERT INTO main.pmcidmap SELECT * FROM extdb.pmcidmap''')
c.execute('''INSERT INTO main.meta SELECT * FROM extdb.meta''')
c.execute('''INSERT INTO main.authors SELECT * FROM extdb.authors''')
c.execute('''INSERT INTO main.keywords SELECT * FROM extdb.keywords''')
c.execute('''INSERT INTO main.abstracts SELECT * FROM extdb.abstracts''')
c.execute('''DETACH DATABASE 'extdb' ''')

#merge file 3
c.execute('''ATTACH DATABASE 'pmcv2-IN.db' AS 'extdb' ''')
c.execute('''INSERT INTO main.refs SELECT * FROM extdb.refs''')
c.execute('''INSERT INTO main.pmcidmap SELECT * FROM extdb.pmcidmap''')
c.execute('''INSERT INTO main.meta SELECT * FROM extdb.meta''')
c.execute('''INSERT INTO main.authors SELECT * FROM extdb.authors''')
c.execute('''INSERT INTO main.keywords SELECT * FROM extdb.keywords''')
c.execute('''INSERT INTO main.abstracts SELECT * FROM extdb.abstracts''')
c.execute('''DETACH DATABASE 'extdb' ''')

#merge file 4
c.execute('''ATTACH DATABASE 'pmcv2-OZ.db' AS 'extdb' ''')
c.execute('''INSERT INTO main.refs SELECT * FROM extdb.refs''')
c.execute('''INSERT INTO main.pmcidmap SELECT * FROM extdb.pmcidmap''')
c.execute('''INSERT INTO main.meta SELECT * FROM extdb.meta''')
c.execute('''INSERT INTO main.authors SELECT * FROM extdb.authors''')
c.execute('''INSERT INTO main.keywords SELECT * FROM extdb.keywords''')
c.execute('''INSERT INTO main.abstracts SELECT * FROM extdb.abstracts''')
c.execute('''DETACH DATABASE 'extdb' ''')

c.execute('''COMMIT''')
c.close()


    

    




---------------------------------------------------------------------------
OperationalError                          Traceback (most recent call last)
<ipython-input-1-7204b60d022d> in <module>()
     49 c.execute('''DETACH DATABASE 'extdb' ''')
     50 
---> 51 c.execute('''COMMIT''')
     52 c.close()

OperationalError: cannot commit - no transaction is active