I want to execute an SQL script against a MSSQL server. In the script I have created table variable by selecting data from a table, then get the data from the variable. But it returns an array with no values.
SQL:
DECLARE #ProductTotals TABLE
(
ProductID int,
Revenue money
)
INSERT INTO #ProductTotals (ProductID, Revenue)
SELECT ProductID, SUM(UnitPrice * Quantity)
FROM [Order Details]
SELECT * FROM #ProductTotals
Python:
data = connection_to_database.execute(sqlFile)
for i in data:
print(i)
Related
I am trying to insert data into a table created in oracle sql using python. It temporarily inserts data into the table but as soon as the python process ends , the data is deleted.
def submit_button(roll_no,name,marks):
sql_query = 'INSERT INTO assignment_7 VALUES (:r,:n,:m)'
c.execute(sql_query,[int(roll_no),name,int(marks)])
c.execute('SELECT * FROM assignment_7')
for rows in c:
print(rows[0],'-',rows[1],'-',rows[2])
For example if (12,'aryan',20) are inserted into the table , the print statement works , but actually no data gets inserted when I check the table itself .
Name Null? Type
ROLL_NO NOT NULL NUMBER
STUDENT_NAME VARCHAR2(30)
MARKS NUMBER
try to add c.commit
def submit_button(roll_no,name,marks):
sql_query = 'INSERT INTO assignment_7 VALUES (:r,:n,:m)'
c.execute(sql_query,[int(roll_no),name,int(marks)])
c.commit
c.execute('SELECT * FROM assignment_7')
for rows in c:
print(rows[0],'-',rows[1],'-',rows[2])
I want to insert a record into usage_information while getting the machine_id from machines tables
How the query should be?
I'm using something like this for selecting from both tables
cur.execute(
'''SELECT U.timestamp, M.hostname, M.up_time,
U.cpu_utilization, U.running_processes,
U.total_memory, U.available_memory,
U.used_memory, U.total_disk_capacity,
U.free_disk_space, U.used_disk_space,
U.network_requests_sent,
U.network_requests_received
FROM usage_information U, machines M
WHERE U.machine_id = M.machine_id
'''
)
I am connecting to Snowflake to query row count data of view table from Snowflake. I am also querying metadata related to View table. My Query looks like below. I was wondering if I can iterate through UNION ALL statement using python ? When I try to run my below query I received an error that says "view_table_3" does not exist.
Thanks in advance for your time and efforts!
Query to get row count for Snowflake view table (with metadata)
view_tables=['view_table1','view_table2','view_table3','view_table4']
print(f""" SELECT * FROM (SELECT TABLE_SCHEMA,TABLE_NAME,CREATED,LAST_ALTERED FROM SCHEMA='INFORMATION_SCHEMA.VIEWS' WHERE TABLE_SCHEMA='MY_SCHEMA' AND TABLE_NAME IN ({','.join("'" +x+ "'" for x in view_tables)})) t1
LEFT JOIN
(SELECT 'view_table1' table_name2, count(*) as view_row_count from MY_DB.SCHEMA.view_table1
UNION ALL SELECT {','.join("'" +x+ "'" for x in view_tables[1:])},count(*) as view_row_count from MY_DB.SCHEMA.{','.join("" +x+ "" for x.replace("'"," ") in view_tables)})t2
on t1.TABLE_NAME =t2.table_name2 """)
If you want to make a union dynamically, put the entire SELECT query inside the generator, and then join them with ' UNION '.
sql = f'''SELECT * FROM INFORMATION_SCHEMA.VIEWS AS v
LEFT JOIN (
{' UNION '.join(f"SELECT '{table}' AS table_name2, COUNT(*) AS view_row_count FROM MY_SCHEMA.{table}" for table in view_tables)}
) AS t2 ON v.TABLE_NAME = t2.table_name2
WHERE v.TABLE_NAME IN ({','.join(f"'{table}'" for table in view_tables)})
'''
print(sql);
I have a sqlite database named StudentDB which has 3 columns Roll number, Name, Marks. Now I want to fetch only the columns that user selects in the IDE. User can select one column or two or all the three. How can I alter the query accordingly using Python?
I tried:
import sqlite3
sel={"Roll Number":12}
query = 'select * from StudentDB Where({seq})'.format(seq=','.join(['?']*len(sel))),[i for k,i in sel.items()]
con = sqlite3.connect(database)
cur = con.cursor()
cur.execute(query)
all_data = cur.fetchall()
all_data
I am getting:
operation parameter must be str
You should control the text of the query. The where clause shall allways be in the form WHERE colname=value [AND colname2=...] or (better) WHERE colname=? [AND ...] if you want to build a parameterized query.
So you want:
query = 'select * from StudentDB Where ' + ' AND '.join('"{}"=?'.format(col)
for col in sel.keys())
...
cur.execute(query, tuple(sel.values()))
In your code, the query is now a tuple instead of str and that is why the error.
I assume you want to execute a query like below -
select * from StudentDB Where "Roll number"=?
Then you can change the sql query like this (assuming you want and and not or) -
query = "select * from StudentDB Where {seq}".format(seq=" and ".join('"{}"=?'.format(k) for k in sel.keys()))
and execute the query like -
cur.execute(query, tuple(sel.values()))
Please make sure in your code the provided database is defined and contains the database name and studentDB is indeed the table name and not database name.
I want to update a column with SQL server query in python, as you see I am updating the relative column as below:
I have a CSV file with some A values of relative table as below:
CSV file: (a.csv)
ART-B-C-ART0015-D-E01
ADC-B-C-ADC00112-V-E01
Python Code: (create Name Value)
ff = pd.read_csv("C:\\a.csv",encoding='cp1252')
ff["Name"]= df["A"].str.extract(r'([a-zA-Z]{3}\d{4,5})') + "-A"
Result of python Code:
ART0015-A
ADC00112-A
Table :
A Name FamilyName
ART-B-C-ART0015-D-E01 NULL ART
ADC-B-C-ADC00112-V-E01 NULL ADC00112
Also A is a column in my table (Not all of the A records but some of them) and based on A value I want to update Name column.
My database is SQL Server and I don't know how to update in Name Column in SQL Server where the A value in the csv file is equal to A in the relative table.
Code in Python:
conn = pyodbc.connect('Driver={SQL Server}; Server=ipaddress; Database=dbname; UID=username; PWD= {password};')
cursor = conn.cursor()
conn.commit()
for row in ff.itertuples():
cursor.execute('''UPDATE database.dbo.tablename SET Name where ?
)
conn.commit()
Expected result in table
A Name FamilyName
ART-B-C-ART0015-D-E01 ART0015-A ART
ADC-B-C-ADC00112-V-E01 ADC00112-A ADC00112
I would use an SQL temp table and inner join to update the values. This will work for only updating a subset of records in your SQL table. It can also be efficient at updating many records.
SQL Cursor
# reduce number of calls to server on inserts
cursor.fast_executemany = True
Create Temporary Table
statement = "CREATE TABLE #temp_tablename(A VARCHAR(200), Name VARCHAR(200))"
cursor.execute(statement)
Insert Values into a Temporary Table
# insert only the key and the updated values
subset = ff[['A','Name']]
# form SQL insert statement
columns = ", ".join(subset.columns)
values = '('+', '.join(['?']*len(subset.columns))+')'
# insert
statement = "INSERT INTO #temp_tablename ("+columns+") VALUES "+values
insert = [tuple(x) for x in subset.values]
cursor.executemany(statement, insert)
Update Values in Main Table from Temporary Table
statement = '''
UPDATE
tablename
SET
u.Name
FROM
tablename AS t
INNER JOIN
#temp_tablename AS u
ON
u.A=t.A;
'''
cursor.execute(statement)
Drop Temporary Table
cursor.execute("DROP TABLE #temp_tablename")