The problem now is that I can only enter one record. No errors are recorded. It just takes the first record from one database and puts in the other database. I am trying to create a machine usable database from the user interface database. I will try to transfer around 100 records once it is working. I would appreciate in comments or suggestions. Thank you!
import sqlite3
sql = 'INSERT INTO heavenStream (scene, cascade, enclosure, sensor, streamer, dither) VALUES (?, ?, ?, ?, ?, ?)'
def dropTable(crs,conn):
crs.execute("DROP TABLE IF EXISTS heavenStream")
def createTable(crs,conn):
sql ='''CREATE TABLE heavenStream(
id INTEGER PRIMARY KEY AUTOINCREMENT,
scene TEXT,
cascade TEXT,
enclosure TEXT,
sensor TEXT,
streamer TEXT,
dither TEXT,
timeStream TEXT,
streamTime TEXT
)'''
crs.execute(sql)
print("Table created successfully........")
def insert_one(conn, crs):
crs.execute("SELECT * FROM animalStream")
for row in crs:
scene = row[1]
cascade = row[2]
enclosure = row[3]
sensor = row[4]
streamer = row[5]
dither = row[6]
print(f"{row[1]} {row[2]} {row[3]} {row[4]} {row[5]} {row[6]}")
try:
crs.execute(sql, (scene, cascade, enclosure,
sensor,streamer,dither))
except sqlite3.IntegrityError as err:
print('sqlite error: ', err.args[0]) # column name is
not unique
conn.commit()
def main():
conn = sqlite3.connect("/home/harry/interface/wildlife.db")
crs = conn.cursor()
dropTable(crs,conn)
createTable(crs,conn)
insert_one(conn, crs)
# conn.commit()
conn.close()
print('done')
main()
The user interface database has had records deleted. There is one record with an id of 64 and the rest are in the 90's.
The cursor (crs) changes here
crs.execute(sql, (scene, cascade, enclosure,sensor,streamer,dither))
after the first insert. Therefore, there are "no more rows to fetch" in the orginal crs.
One solution would be to instantiate another cursor for the insert. Another solution would be to fetchall() the rows into a variable and iterate over that variable as with:
rows = crs.execute("SELECT * FROM animalStream").fetchall()
for row in rows:
Related
I created one-to-many relationship table and according to the sqlite3 documentation I can't insert value into the child table if the referenced table column value in the parent table does not exist.
import sqlite3
class Database:
def __init__(self, database_name):
self.database_name = database_name
def create_table(self, table_name, *columns):
columns = ", ".join(columns)
conn = sqlite3.connect(self.database_name)
cursor = conn.cursor()
_SQL = f"CREATE TABLE IF NOT EXISTS {table_name}({columns})"
cursor.execute(_SQL)
conn.commit()
cursor.close()
conn.close()
def insert_values(self, table_name, values, *columns):
dynamic_values = ('?, ' * len(columns))[0:-2]
columns = ", ".join(columns)
conn = sqlite3.connect(self.database_name)
cursor = conn.cursor()
_SQL = f"INSERT INTO {table_name}({columns}) VALUES ({dynamic_values})"
cursor.execute(_SQL, values)
conn.commit()
cursor.close()
conn.close()
def view_values(self, table_name, *columns):
columns = ", ".join(columns)
conn = sqlite3.connect(self.database_name)
cursor = conn.cursor()
_SQL = f"SELECT {columns} FROM {table_name}"
cursor.execute(_SQL)
the_data = cursor.fetchall()
cursor.close()
conn.close()
return the_data
data = Database("games.db")
#
# data.create_table("supplier_groups", "group_id integer PRIMARY KEY", "group_name text NOT NULL")
#
data.insert_values("supplier_groups", ("Domestic", ), "group_name")
# data.create_table("suppliers ", "supplier_id INTEGER PRIMARY KEY",
# "supplier_name TEXT NOT NULL",
# "group_id INTEGER NOT NULL, "
# "FOREIGN KEY (group_id) REFERENCES supplier_groups (group_id)")
data.insert_values("suppliers", ('ABC Inc.', 9), "supplier_name", "group_id")
as you see on this line: data.insert_values("supplier_groups", ("Domestic", ), "group_name") - I'm inserting a value into supplier_groups table
and then right here: data.insert_values("suppliers", ('ABC Inc.', 9), "supplier_name", "group_id") - I'm inserting value into suppliers table with the group_id that does not exist in the group_suppliers table. Python executes it successfully and adds value to the database, however when attemping to execute this command in SQLITE browser I get this error:
Execution finished with errors. Result: FOREIGN KEY constraint failed which is what python should also have done instead of adding it into the database.
So, could anyone explain me what's going on here? Do I understand something in the wrong way? Help would be appreciated
From Section 2. Enabling Foreign Key Support in the sqlite doc:
Assuming the library is compiled with foreign key constraints enabled, it must still be enabled by the application at runtime, using the PRAGMA foreign_keys command. For example:
sqlite> PRAGMA foreign_keys = ON;
I'm trying to create a code piece that inserts an object I've created to store data in a very specific way into an SQL table as a blob type, and it keeps giving me an ' sqlite3.InterfaceError: Error binding parameter 1 - probably unsupported type.' error.
Has any of you encountered something similar before? Do you have any ideas how to deal with it?
conn = sqlite3.connect('my_database.db')
c = conn.cursor()
params = (self.question_id, i) #i is the object in question
c.execute('''
INSERT INTO '''+self.current_test_name+''' VALUES (?, ?)
''',params)
conn.commit()
conn.close()
For starters, this would be a more appropriate execute statement as it is way cleaner:
c.execute("INSERT INTO "+self.current_test_name+" VALUES (?, ?)", (self.question_id, i))
You are also missing the table you are inserting into (or the columns if self.current_test_name is the table name.)
Also, Is the column in the database setup to handle the data type for the provided input for self.question_id and i? (Not expecting TEXT when you provided INT?)
Example of a working script to insert into a table that has 2 columns named test and test2:
import sqlite3
conn = sqlite3.connect('my_database.db')
c = conn.cursor()
c.execute("CREATE TABLE IF NOT EXISTS test(test INT, test2 INT)")
conn.commit()
for i in range(10):
params = (i, i) # i is the object in question
c.execute("INSERT INTO test (test, test2) VALUES (?, ?)", params)
conn.commit()
conn.close()
I made new column with NULL values called 'id' in table. Now I want to add data to it from list. It holds about 130k elements.
I tried with insert, it returned error:
conn = create_connection(xml_db)
cursor = conn.cursor()
with conn:
cursor.execute("ALTER TABLE xml_table ADD COLUMN id integer")
for data in ssetId:
cursor.execute("INSERT INTO xml_table(id) VALUES (?)", (data,))
conn.commit()
I also tried with update:
conn = create_connection(xml_db)
cursor = conn.cursor()
with conn:
cursor.execute("ALTER TABLE xml_table ADD COLUMN id INTEGER")
for data in ssetId:
cursor.execute("UPDATE xml_table SET ('id' = ?)", (data,))
conn.commit()
What is incorrect here ?
EDIT for clarification.
The table was already existing, filled with data. I want to add column 'id' with custom values to it.
Heres an example similar to yours which may be useful.
import sqlite3
conn = sqlite3.connect("xml.db")
cursor = conn.cursor()
with conn:
# for testing purposes, remove this or else the table gets dropped whenever the file is loaded
cursor.execute("drop table if exists xml_table")
# create table with some other field
cursor.execute("create table if not exists xml_table (other_field integer not null)")
for other_data in range(5):
cursor.execute("INSERT INTO xml_table (other_field) VALUES (?)", (other_data,))
# add id field
cursor.execute("ALTER TABLE xml_table ADD COLUMN id integer")
# make sure the table exists
res = cursor.execute("SELECT name FROM sqlite_master WHERE type='table'")
print("Table Name: {}".format(res.fetchone()[0]))
# add data to the table
for data in range(5):
cursor.execute("UPDATE xml_table SET id = ? WHERE other_field = ?", (data, data))
# if you must insert an id, you must specify a other_field value as well, since other_field must be not null
cursor.execute("insert into xml_table (id, other_field) VALUES (? ,?)", (100, 105))
# make sure data exists
res = cursor.execute("SELECT id, other_field FROM xml_table")
for id_result in res:
print(id_result)
conn.commit()
conn.close()
As I stated in the comment below, since one of your rows has a NOT NULL constraint on it, no rows can exist in the table that have that column NULL. In the example above other_field is specified NOT NULL, therefore there can be no rows that have NULL values in the column other_field. Any deviation from this would be an IntegrityError.
Output:
Table Name: xml_table
(0, 0)
(1, 1)
(2, 2)
(3, 3)
(4, 4)
(100, 105)
Hi..while using the follwing code i am getting duplicate entries in my table..
Please suggest some method to avoid such duplicate entries..!!
Is there any other mode of INSERT query to acheive duplication free tables..???
import psycopg2
def connect():
con=psycopg2.connect("dbname='book_store' user='postgres' password='5283' host='localhost' port='5432' ")
cur=con.cursor()
cur.execute("CREATE TABLE if not exists books(id SERIAL PRIMARY KEY,title TEXT NOT NULL,author TEXT NOT NULL,year integer NOT NULL,isbn integer NOT NULL)")
con.commit()
con.close()
def insert(title,author,year,isbn):
con=psycopg2.connect("dbname='book_store' user='postgres' password='5283' host='localhost' port='5432'")
cur=con.cursor()
cur.execute("INSERT INTO books(title,author,year,isbn) VALUES(%s,%s,%s,%s)",(title,author,year,isbn))
con.commit()
con.close()
connect()
insert("the sun","helen",1997,23456777)
insert("the sun","helen",1997,23456777)
Here the same entry gets added again..where i want my code to neglect such duplication..!!!
Ideally there should be primary key or Unique key constraint defined on the table to avoid duplicates but if you want to insert only if that record doesn't exists then you can use below insert statement with select & where not exists clause
INSERT INTO books(title,author,year,isbn) select #title,#author,#year,#isbn from books where
not exists (select 1 from books where title=#title and author=#author and year=#year and isbn=#isbn);
In where condition should check for Primary OR Unique key columns instead of all the columns.
when i inserted the first value and next time when i give different value, the old one gets updated with the new one. I am trying to insert mutiple values and store them without getting them updated. How do i do that?
import pymysql
conn = pymysql.connect(host='127.0.0.1', user='root', passwd='nazaf123', db='nazafdatabase')
cur = conn.cursor()
cur.execute("DROP TABLE IF EXISTS EMPLOYEE")
sql = """CREATE TABLE EMPLOYEE (
FIRST_NAME CHAR(20) NOT NULL,
LAST_NAME CHAR(20),
AGE INT,
SEX CHAR(2),
SALARY FLOAT )"""
cur.execute(sql)
sql = """INSERT INTO EMPLOYEE(FIRST_NAME, LAST_NAME, AGE, SEX, SALARY)
VALUES ('Nazaf', 'Anwar', 22, 'M', 10000)"""
try:
cur.execute(sql)
conn.commit()
except:
conn.rollback()
cur.execute("""SELECT * FROM employee;""")
print(cur.fetchall())
cur.close()
conn.close()
I do not see any code here which does actual updating, unless you can clarify what you are seeing and what you expect to see the following may not help here.
Right now you are deleting a table and recreating it, this will remove all previous data from it. Your Insert statement will typically never alter previous rows for which none exist so I am going to take a guess based on your question that you may have an Update Employee Set (New Data) which would alter the previous record.
To insert new data you will need to perform another Insert command. If you are performing an Update command it will update all records and not insert a new row. Typically Update is followed at the end with a where (Conditional Statement) which lets you limit how the records are modified.
I don't have python or SQL database at this hour this should work. I added onto your provided code however I removed the authentication data.
import pymysql
conn = pymysql.connect({Connection Data here})
cur = conn.cursor()
sql = """INSERT INTO EMPLOYEE(FIRST_NAME, LAST_NAME, AGE, SEX, SALARY) VALUES ('Nazaf', 'Anwar', 22, 'M', 10000)"""
try:
cur.execute(sql)
conn.commit()
except:
conn.rollback()
cur.execute("""SELECT * FROM employee;""")
#You should see the current data here.
sql = """INSERT INTO EMPLOYEE(FIRST_NAME, LAST_NAME, AGE, SEX, SALARY) VALUES ('John', 'Doe', 44, 'M', 300000)"""
cur.execute(sql)
cur.execute("""SELECT * FROM employee;""")
#You should see both Nazaf and John
sql = """UPDATE EMPLOYEE SET SALARY=30 WHERE FIRST_NAME='John'"""
cur.execute(sql)
cur.execute("""SELECT * FROM employee;""")
#You should see both Nazaf and John, however John's salary will be 30
sql = """UPDATE EMPLOYEE SET FIRST_NAME='BOB'"""
cur.execute(sql)
cur.execute("""SELECT * FROM employee;""")
#You should see the first names changed to bob.
print(cur.fetchall())
cur.close()
conn.close()