insert or replace statement not working with sqlite3 and python - python

Everytime I run this through the python interpreter it writes new values. for example:
name = ben
age = 10
phone = 42045042
If I run it 10 times. I get 10 duplicates in my database. I know it has to be an easy fix, but I've been working on this for hours and can't figure it out.
conn = sqlite3.connect('addressbook.db')
cur=conn.cursor()
conn.execute('''
CREATE TABLE IF NOT EXISTS people(name TEXT,
age TEXT, phone TEXT, fblink TEXT)''')
conn.execute("INSERT OR REPLACE INTO people values (?, ?, ?, ?)", ben.displayPerson())
cursor = conn.execute("SELECT name, age, phone, fblink from people")
for row in cursor:
print "NAME = ", row[0]
print "AGE = ", row[1]
print "PHONE = ", row[2]
print "FACEBOOK LINK = ", row[3], "\n"
cur.close()
conn.commit()
conn.close()

There's no primary key field.
Make a primary key field.
For example:
conn.execute('''
CREATE TABLE IF NOT EXISTS people(name TEXT primary key,
age TEXT, phone TEXT, fblink TEXT)''')
REPLACE is executed when UNIQUE constraint violation occurs. Without primary key (or unique ..), it does not happen.

Your table has no primary key, and hence SQLite doesn't know what it should "OR REPLACE" since it has nothing to base replacing on. Add a primary key.

Related

Python-sqlite3 : How to put a python variable in SELECT statement

How can I put a python variable just after the SELECT. The idea is to create a python function with three arguments where you can choose what you what (here, it's the age) from whom (here, it's Mike and James)
conn = sqlite3.connect('test.s3db')
cur = conn.cursor()
cur.execute('''DROP TABLE IF EXISTS people''')
cur.execute('''CREATE TABLE IF NOT EXISTS people
(id INTEGER,
name TEXT,
surname TEXT,
age INTEGER,
alone INTEGER DEFAULT 0);''')
def add_people(id, name, surname, age, alone=0):
cur.executemany('INSERT INTO people (id, name, surname, age, alone) VALUES (?,?,?,?,?)', [(id, name, surname, age, alone)])
conn.commit()
add_people(1, 'SMITH','James',45)
add_people(2,'JOHNSON','Mike',75)
cur.execute('''SELECT (?) FROM people WHERE surname = (?) OR surname = (?)''', ('age','Mike', 'James'))
print(cur.fetchall())
My code return:
[('age',), ('age',)]
instead of :
[(75,), (45,)]
EDIT : I want that what is selected is a variable and not directly written in the query. My goal is to make a function like this one :
def query(what, who_1, who_2):
cur.executemany('''SELECT (?) FROM people WHERE surname = (?) OR surname = (?)''', (what, who_1, who_2))
return cur.fetchall()
Thank you in advance for your answers !
This takes the data you need as argument of select_data_of
import sqlite3
def add_people(id, name, surname, age, alone=0):
cur.executemany('INSERT INTO people (id, name, surname, age, alone) VALUES (?,?,?,?,?)', [(id, name, surname, age, alone)])
conn.commit()
def select_data_of(names, data="age"):
select = []
for name in names:
cur.execute(f'''SELECT [{data}] FROM people WHERE surname = (?)''', (name, ))
select.append(cur.fetchall()[0])
return select
with sqlite3.connect('test.s3db') as conn:
cur = conn.cursor()
cur.execute('''DROP TABLE IF EXISTS people''')
cur.execute('''CREATE TABLE IF NOT EXISTS people
(id INTEGER,
name TEXT,
surname TEXT,
age INTEGER,
alone INTEGER DEFAULT 0);''')
add_people(2,'JOHNSON','Mike',75)
add_people(1, 'SMITH','James',45)
data = select_data_of(("Mike", "James"), data="age")
print(data)
OUT:
[(75,), (45,)]
I think your select query is wrong because of the 'ages' parameter, this new query will work.
Try
cur.execute("SELECT [age] FROM people WHERE surname = 'Mike' OR surname = 'James")

Taking value from column in one sqlite3 table and inserting into another

I am trying to add a feature to my program where a teacher sets homework to users from a class they've made. There is a table for users where each user has a unique UserID, classname, firstname and surname. I am trying to take the userIDs of students who are in a certain class, and insert them into a HomeworkSet table. I am able to retrieve the userIDs successfully, but when I insert them into the HomeworkSet table, the values appear as (for example) ('2a1910e919a84230bfc2a7111160cade',), and I am not sure how I am meant to remove the brackets and apostraphes.
def Class_sethw():
homeworktoset = Homework_To_Set.get()
#print (homeworktoset)
conn = sqlite3.connect('MyComputerScience.db')
c = conn.cursor()
homeworkID = c.execute("SELECT HWID FROM HomeworkInfo WHERE HomeworkName = ?", (homeworktoset, )).fetchone()
print (homeworkID)
c.execute("SELECT UserID FROM users WHERE ClassName = ?", (ClassName_SetHWR, ))
homeworksetlist = c.fetchall()
print (homeworksetlist)
for i in (homeworksetlist):
#x = i
#firstname, lastname = x.split(" ")
c.execute('insert INTO HomeworkSet (HWID, StudentID)VALUES(?,?);', ((homeworkID[0]), str(i)))
conn.commit()
Label(sethw, text = "Homework Set!", fg = "GREEN").place(relx=0.205, rely=0.445, height=34, width=97)
This is the code I have used.
You should change this line:
for i in (homeworksetlist):
to:
for i in homeworksetlist:

No data inserted after successful SQLite statement within Python

Extension from previous question
Attempting to insert SQL values into database after pulling from XML file, but none seem to be appearing in database after insert statement embedded in Python code. Without the SQL section included, the entries are printed as expected. I am not getting an error in my Python environment (Anaconda Navigator), so totally lost on how the queries were processed, but nothing was entered! I tried a basic select statement to display the table, but get an empty table back.
Select Query
%sql SELECT * FROM publication;
Main Python code
import sqlite3
con = sqlite3.connect("publications.db")
cur = con.cursor()
from xml.dom import minidom
xmldoc = minidom.parse("test.xml")
#loop through <pub> tags to find number of pubs to grab
root = xmldoc.getElementsByTagName("root")[0]
pubs = [a.firstChild.data for a in root.getElementsByTagName("pub")]
num_pubs = len(pubs)
count = 0
while(count < num_pubs):
#get data from each <pub> tag
temp_pub = root.getElementsByTagName("pub")[count]
temp_ID = temp_pub.getElementsByTagName("ID")[0].firstChild.data
temp_title = temp_pub.getElementsByTagName("title")[0].firstChild.data
temp_year = temp_pub.getElementsByTagName("year")[0].firstChild.data
temp_booktitle = temp_pub.getElementsByTagName("booktitle")[0].firstChild.data
temp_pages = temp_pub.getElementsByTagName("pages")[0].firstChild.data
temp_authors = temp_pub.getElementsByTagName("authors")[0]
temp_author_array = [a.firstChild.data for a in temp_authors.getElementsByTagName("author")]
num_authors = len(temp_author_array)
count = count + 1
#process results into sqlite
pub_params = (temp_ID, temp_title)
cur.execute("INSERT INTO publication (id, ptitle) VALUES (?, ?)", pub_params)
journal_params = (temp_booktitle, temp_pages, temp_year)
cur.execute("INSERT INTO journal (jtitle, pages, year) VALUES (?, ?, ?)", journal_params)
x = 0
while(x < num_authors):
cur.execute("INSERT OR IGNORE INTO authors (name) VALUES (?)", (temp_author_array[x],))
x = x + 1
#display results
print("\nEntry processed: ", count)
print("------------------\nPublication ID: ", temp_ID)
print("Publication Title: ", temp_title)
print("Year: ", temp_year)
print("Journal title: ", temp_booktitle)
print("Pages: ", temp_pages)
i = 0
print("Authors: ")
while(i < num_authors):
print("-",temp_author_array[i])
i = i + 1
print("\nNumber of entries processed: ", count)
SQL queries
%%sql
DROP TABLE IF EXISTS publication;
CREATE TABLE publication(
id INT PRIMARY KEY NOT NULL,
ptitle VARCHAR NOT NULL
);
/* Author Entity set and writes_for relationship */
DROP TABLE IF EXISTS authors;
CREATE TABLE authors(
name VARCHAR(200) PRIMARY KEY NOT NULL,
pub_id INT,
pub_title VARCHAR(200),
FOREIGN KEY(pub_id, pub_title) REFERENCES publication(id, ptitle)
);
/* Journal Entity set and apart_of relationship */
DROP TABLE IF EXISTS journal;
CREATE TABLE journal(
jtitle VARCHAR(200) PRIMARY KEY NOT NULL,
pages INT,
year INT(4),
pub_id INT,
pub_title VARCHAR(200),
FOREIGN KEY(pub_id, pub_title) REFERENCES publication(id, ptitle)
);
/* Wrote relationship b/w journal & authors */
DROP TABLE IF EXISTS wrote;
CREATE TABLE wrote(
name VARCHAR(100) NOT NULL,
jtitle VARCHAR(50) NOT NULL,
PRIMARY KEY(name, jtitle),
FOREIGN KEY(name) REFERENCES authors(name),
FOREIGN KEY(jtitle) REFERENCES journal(jtitle)
);
You need to call con.commit() in order to commit the data to the database. If you use the connection as a context manager (with con:), the connection will commit any changes you make (or roll them back if there is an error).
Explicitly closing the connection is also a good practice.
It looks like you are forgetting to commit and close the connection. You need to call these two functions in order to properly close the connection and to save the work you have done to the database.
conn.commit()
conn.close()

Insert Data Into A Table Using The Same Foreign Key Value

I'm using SQL Server, Python, pypyodbc.
The tables I have are:
tbl_User: id, owner
tbl_UserPhone: id, number, user_id
user_id is the primary key of User and the foreign key of UserPhone.
I'm trying to insert 2 different phones to the same user_id using pypyodbc.
This is one of the things I tried that did not work:
cursor = connection.cursor()
SQLCommand = ("INSERT INTO tbl_UserPhones"
"(id,number,user_id)"
" VALUES (?,?,?)")
values = [userphone_index, user_phone,"((SELECT id from tbl_User where id = %d))" % user_id_index]
cursor.execute(SQLCommand, values)
cursor.commit()
Based on your comments, you have an identity column in tbl_UserPhones. Based on the column names I'm guessing it's the ID column.
The exception you get is very clear - you can't insert data into an identity column without specifically setting identity_insert to on before your insert statement. Basically, messing around with identity columns is bad practice. it's better to let Sql server to use it's built in capabilities and handle the insert to the identity column automatically.
You need to change your insert statement to not include the id column:
Instead of
SQLCommand = ("INSERT INTO tbl_UserPhones"
"(id,number,user_id)"
" VALUES (?,?,?)")
values = [userphone_index, user_phone,"((SELECT id from tbl_User where id = %d))" % user_id_index]
try this:
SQLCommand = ("INSERT INTO tbl_UserPhones"
"(number,user_id)"
" VALUES (?,?)")
values = [user_phone,"((SELECT id from tbl_User where id = %d))" % user_id_index]
SQLCommand = ("INSERT INTO tbl_UserPhones"
"(id,number,user_id)"
" VALUES (?,?,?)")
user_sqlCommand = cursor.execute("(SELECT id FROM tbl_User WHERE id = %d)" % user_index).fetchone()[0]
values = [userphone_index, user_phone, user_sqlCommand]
This was the solution.

SQLite: INSERT or REPLACE w/ null PRIMARY KEY

I am trying to INSERT or REPLACE INTO t1 if the name is already there. I understand if the id is set then replace will work, but I need it to react to name.
import sqlite3
def insert(name):
cur.execute('INSERT OR REPLACE INTO t1(name) VALUES(?)', [name])
def select():
return cur.execute('SELECT * FROM t1').fetchall()
conn = sqlite3.connect('test')
cur = conn.cursor()
cur.execute('DROP TABLE IF EXISTS t1')
cur.execute('''CREATE TABLE IF NOT EXISTS t1(
id INTEGER PRIMARY KEY,
name TEXT NOT NULL
)''')
insert('jack')
insert('jack')
insert('jack')
print select()
output
[(1, u'jack'), (2, u'jack'), (3, u'jack')]
INSERT or REPLACE ... will do replace only if there are collisions. And as your name column isnt collidable, this event cannot accur (at least not on name). You need to make name collidable:
CREATE UNIQUE INDEX IF NOT EXISTS iname ON t1 (name)
Also note that you dont need to have id column, because sqlite3 has ROWID on every table.

Categories

Resources