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how to convert multiple insert into one insert using python

I have a sql file in which there are many insert sql to the same table:
insert into tbname
values (xxx1);
insert into tbname values (xxx2);
insert into
tbname values (xxx3);
...
how to convert this file into a new file containing one sql like :
insert into tbname (xxx1),(xxx2),(xxx3)...;
Due to different insert formats as above in the sql file, it make hard to use regular express in python.

If you want to insert multiple rows into the table use executemany() method.
mydb = mysql.connector.connect(
host="localhost",
user="yourusername",
passwd="yourpassword",
database="mydatabase"
)
mycursor = mydb.cursor()
sql = "INSERT INTO tbname VALUES (%s)"
val = [
('xx1'),
('xx2'),
('xx3')
]
mycursor.executemany(sql, val)
mydb.commit()
For more info, follow this.

Open your file to a string and use split to get all values in a table and then again to a string. Something like:
s = "insert into tbname values (val1, val2);insert into tbname values (val3, val4);insert into tbname values (val5, val6);"
values = s.replace(";insert into tbname values", ', ')
It's an anorthodox method but could work in your case to get it in one insert.

python database insert formatting

I am trying to insert into a postgresql database in python 3.6 and currently am trying to execute this line
cur.execute("INSERT INTO "+table_name+"(price, buy, sell, timestamp) VALUES (%s, %s, %s, %s)",(exchange_rate, buy_rate, sell_rate, date))
but every time it tries to run the table name has ' ' around it so it turns out like INSERT INTO table_name('12', ..., ..., ...) ... instead of
INSERT INTO table_name(12, ..., ..., ...) ... how can I make the string formatter leave the quotes out or remove them or something? It is causing a syntax error around the 12 because it doesn't need the single quotes.

Use it with triple quotes. Also you may pass table_name as a element of second parameter, too.
cur.execute("""INSERT INTO %s (price, buy, sell, timestamp) VALUES (%s, %s, %s, %s)""",(table_name, exchange_rate, buy_rate, sell_rate, date))
More detailed approach;
Triple qoutes give developers a change to write SQL query as multi-lines.
Also it allows you to use single and double qoutes without escaping from them. (It is beneficiary for complex SQL Queries but you don't need that on your case)

Use the new string formatting to have a clean representation. %s is explicitly converting to a string, you don't want that. Format chooses the most fitting type for you.
table_name = "myTable"
exchange_rate = 1
buy_rate = 2
sell_rate = 3
date = 123
x = "INSERT INTO {0} (price, buy, sell, timestamp) VALUES ({1}, {2}, {2}, {4})".format(
table_name, exchange_rate, buy_rate, sell_rate, date)
print x
>INSERT INTO myTable (price, buy, sell, timestamp) VALUES (1, 2, 2, 123)

Using insert query in python for postgresql

I want to insert values to a database using python, but it's failed. This is my code:
try:
cur.execute("""INSERT INTO tb_distance (objek1, objek2, distance) VALUES ('%s','%s','%d')""", (data[i].jenis, data[k].jenis, distance))
conn.commit()
except:
conn.rollback()
print 'cannot insert into database'

Thank you, I fixed my problem, I replace (,) to (%) before list of values. This is my code and run well:
cur.execute("""INSERT INTO tb_distance (objek1, objek2, distance) VALUES ('%s','%s','%f')""" % (data[i].jenis, data[k].jenis, distance))

Remove quotes around the placeholders ('%s' -> %s, '%d' -> %d):
cur.execute(
"INSERT INTO tb_distance (objek1, objek2, distance) VALUES (%s, %s, %d)",
(data[i].jenis, data[k].jenis, distance)
)

psycopg2: Insert a numpy array of strings into an PostgreSQL table

Please consider me to be a complete novice with psycopg2. My aim is to insert a 1D numpy array of dtype object (where the elements are only strings) into a postgresQL table. My main program saves the fields as strings in the numpy array. I then want to add each separate element to a column in the postgresqL table (or if you prefer, the the 1d Array is one row). Please note, the actual array has 36 elements! I need a method to put them all in.
I am using the cur.execute command although I believe there is some problem with the string conversion.
Array=np.empty(3,dype=object)
Array[0]='Hello'
Array[1]='Tea?'
Array[2]='Bye'
statement= "INSERT INTO testlog (field1,field2,field3) VALUES (%s)" #Etc.
cur.execute(statement,Array)
I get error:
cur.execute(statement,Array)
TypeError: not all arguments converted during string formatting
Also tried:
cur.executemany('INSERT INTO testlog VALUES ( %s )', [[v] for v in Array ]
Thanks

Your statement should contain place holder for all values:
statement= "INSERT INTO testlog (field1,field2,field3) VALUES (%s, %s, %s)"
For Example:
=# create table testlog (field1 varchar(50), field2 varchar(50), field3 varchar(50))`;
then in the python shell (note dtype not dype:
Array=np.empty(3,dtype=object)
Array[0]='Hello'
Array[1]='Tea?'
Array[2]='Bye'
sql = "INSERT INTO testlog (field1, field2, field3) VALUES (%s, %s, %s)"
cur.execute(sql, [f for f in Array])
conn.commit()
And in DB:
select * from testlog;
field1 | field2 | field3
--------+--------+--------
Hello | Tea? | Bye
(1 row)

MySQL syntax error using python to add column to a table

The code i have is:
for key in keys:
cursor.execute("""
ALTER TABLE segment_table ADD %s VARCHAR(40)
""", key)
I get a error telling me my syntax is wrong. When I replace the %s with a actual string the syntax error goes away.
for key in keys:
cursor.execute("""
ALTER TABLE segment_table ADD myColumn VARCHAR(40)
""")
Any help is appreciated.

There is a bit of confusion going here, for several reasons:
(1) mySQL uses the % as a parameter marker -- easily confused with the % in Python's string % (data1, data2, etc)
(2) some people seem not to be aware that parameter markers can be used only where an expression can be used in SQL syntax -- this excludes table names, column names, function names, keywords, etc
(3) code-golf onelinerism
Required SQL: ALTER TABLE segment_table ADD myColumn VARCHAR(40)
Using a parameter doesn't work:
key = "myColumn"
sql = "ALTER TABLE segment_table ADD %s VARCHAR(40)" # col name not OK as parm
cursor.execute(sql, (key, ))
You need to build an acceptable SQL statement, using e.g. Python string formatting:
key = "myColumn"
sql = "ALTER TABLE segment_table ADD %s VARCHAR(40)" % key
cursor.execute(sql)

Shouldn't you do the replacement before feeding it?
query = "ALTER TABLE segment_table ADD %s VARCHAR(40)" % (key)
cursor.execute( query )

when cursor.execute() replace %s in a query string it adds ' ' to the argument values supplied...so when you do
key = 'abc'
cursor.execute("""
ALTER TABLE segment_table ADD %s VARCHAR(40)
""", key)
the query executed is
ALTER TABLE segment_table ADD 'abc' VARCHAR(40)
to which mysql will throw a syntax error coz the column names, table names can be in `` but not ' '
so this will work
query = "ALTER TABLE segment_table ADD %s VARCHAR(40)" % (key)