I am inserting a couple thousand records into a table via the python code below:
values = ''
for row in cursor:
values = values + "(" + self.quoted_comma_separate(row) + "),"
values = values[:-1]
insert_statement = "INSERT INTO t1 ({0}) VALUES {1};".format(
self.comma_separate(members), values)
db = Database()
conn = db.get_db()
cursor = conn.cursor()
cursor.execute(insert_statement)
conn.commit()
conn.close()
When I check the database after it runs none of the records show up in the database. If I go into an MySQL editor and manually commit the transaction all of the records appear. Why is my conn.commit() not working?
The insert statements were fine. Turns out I had another database connection open and it was getting confused and committing to the wrong connection or something like that. Sorry for the pointless question :)
Related
I have parameterized queries with f strings such that the queries will select some data from a series of tables and joins, and I want to insert the resulting set of data into another pre-created table (tables been designed to house these results).
Python executes the code but the query results never show up in my table.
Assuming target_table is already created in singlestore database:
qry_load = 'insert into target_table select * from some_tables'
conn = engine.connect()
trans = conn.begin()
try:
conn.execute(qry_load)
trans.commit()
except:
trans.rollback()
raise
The code executes and acts as if all is ok, but the data never shows up in the target table.
How do I see what singlestore is passing back to better debug what is happening within the database?
Just replace begin() with cursor() function:
conn = engine.connect()
trans = conn.cursor()
If not resolved
1- Verify structure of source and destination tables if they are same or not.
2- remove try ,except and rollback() block so you can know the actual error.
Ex.
qry_load = 'insert into target_table select * from some_tables'
conn = engine.connect()
trans = conn.cursor()
conn.execute(qry_load)
trans.commit()
When I'm using pymysql to perform operations on MySQL database, it seems that all the operations are temporary and only visible to the pymysql connection, which means I can only see the changes through cur.execute('select * from qiushi') and once I cur.close() and conn.close() and log back in using pymysql, everything seems unchanged.
However, when I'm looking at the incremental id numbers, it does increased, but I can't see the rows that were inserted from pymysql connection. It seems that they were automatically deleted?!
Some of my code is here:
import pymysql
try:
conn = pymysql.connect(host='127.0.0.1',port=3306,user='pymysql',passwd='pymysql',charset='utf8')
cur = conn.cursor()
#cur.execute('CREATE TABLE qiushi (id INT NOT NULL AUTO_INCREMENT, content_id BIGINT(10) NOT NULL, content VARCHAR(1000), created TIMESTAMP DEFAULT CURRENT_TIMESTAMP, PRIMARY KEY(id));')
#cur.execute('DESCRIBE content')
#cur.fetchall()
cur.execute('USE qiushibaike')
for _ in range(0,len(content_ids)):
cur.execute("INSERT INTO qiushi (content,content_id) VALUES (\"%s\",%d)"%(jokes[_],int(content_ids[_])))
finally:
cur.close()
conn.close()
I solved the problem by myself...
Because the config is automatically committed, so after each SQL sentence we should commit the changes.
Approach 1:
add cur.commit() after the cur.execute()
Approach 2:
edit the connection config, add autocommit=True
I'm new to mySQL and Python.
I have code to insert data from Python into mySQL,
conn = MySQLdb.connect(host="localhost", user="root", passwd="kokoblack", db="mydb")
for i in range(0,len(allnames)):
try:
query = "INSERT INTO resumes (applicant, jobtitle, lastworkdate, lastupdate, url) values ("
query = query + "'"+allnames[i]+"'," +"'"+alltitles[i]+"',"+ "'"+alldates[i]+"'," + "'"+allupdates[i]+"'," + "'"+alllinks[i]+"')"
x = conn.cursor()
x.execute(query)
row = x.fetchall()
except:
print "error"
It seems to be working fine, because "error" never appears. Instead, many rows of "1L" appear in my Python shell. However, when I go to MySQL, the "resumes" table in "mydb" remains completely empty.
I have no idea what could be wrong, could it be that I am not connected to MySQL's server properly when I'm viewing the table in MySQL? Help please.
(I only use import MySQLdb, is that enough?)
use commit to commit the changes that you have done
MySQLdb has autocommit off by default, which may be confusing at first
You could do commit like this
conn.commit()
or
conn.autocommit(True) Right after the connection is created with the DB
I am trying to add all words of a text file into a column such that one row has one word. my code is as :
import MySQLdb
conn = MySQLdb.connect (host = "localhost",user = "root", db = "pcorpora")
c = conn.cursor()
file = open('C:\Users\Admin\Desktop\english.txt', 'r')
words = list(file.read())
i=0
for value in words:
c.execute("""INSERT INTO tenglish (`english words`) VALUES (%s)""" % (words[i]) i=i+1)`
The code run without error but table is still empty.
You should use commit
c.execute("""INSERT INTO tenglish (`english words`) VALUES (%s)""" % (value))
con.commit()
This method sends a COMMIT statement to the MySQL server, committing
the current transaction. Since by default Connector/Python does not
autocommit, it is important to call this method after every
transaction that modifies data for tables that use transactional
storage engines.
By using Python and cx_Oracle, I am trying to insert rows to a table.
con = cx_Oracle.connect(ORACLE_USER+'/'+PASS+'#'+TNS)
cursor = con.cursor()
...
try:
cursor.executemany("INSERT INTO table(ID,NAME) VALUES(...)"
except cx_Oracle,exc:
error ,=exc.args
print error.code
print error.message
cursor.close()
con.close()
After insert all the rows from an input file, by using select query in cx_Oracle, I can see the inserted rows. However, sqlplus gives no results when I enter "select * from table;"
Is there something that I missed about cx_Oracle or is there a buffer in oracle client that shows the old results with sqlplus when it is connected to a remote db?
Have you committed your insert?
con.commit() #after inserts
or
con.autocommit = true #before inserts
I had an inverted problem: I added rows using sqlquery and after 2 hours of suffering read this post and guess, that I should close my session. I closed the console and managed to get my data!