Getting SQLCODE=-104 on binding a parameter for DB2 query in Python - python-3.x

Question

Assuming the data.xlsx looks like this:
Column_Name | Table_Name
CUST_ID_1 | Table_1
CUST_ID_2 | Table_2
Here are the SQLs that I'm trying to generate by using the bind_param for db2 in Python:
SELECT CUST_ID_1 FROM TABLE_1 WHERE CUST_ID_1 = 12345
SELECT CUST_ID_2 FROM TABLE_2 WHERE CUST_ID_2 = 12345
And this is how Im trying to generate this query:
import ibm_db
import pandas as pd
from pandas import ExcelWriter
from pandas import ExcelFile
validate_sql = "SELECT ? FROM ? WHERE ?=12345"
validate_stmt = ibm_db.prepare(conn, validate_sql)
df = pd.read_excel("data.xlsx", sheet_name='Sheet1')
for i in df.index:
ibm_db.bind_param(validate_stmt, 1, df['Column_Name'][i])
ibm_db.bind_param(validate_stmt, 2, df['Table_Name'][i])
ibm_db.bind_param(validate_stmt, 3, df['Column_Name'][i])
ibm_db.execute(validate_stmt)
validation_result = ibm_db.fetch_both(validate_stmt)
while validation_result != False:
print(validation_result[0])
validation_result = ibm_db.fetch_both(validate_stmt)
When I try to execute this code, Im hitting a SQLCODE=-104 error.
Any idea how the syntax should be for parameter binding?
Thanks,
Ganesh

Answer 1

2 major errors.
1. You can’t use a parameter marker for a table or column name (2-nd & 3-rd parameters).
2. You must specify the data type of the parameter marker, if it’s not possible to understand it from the query (1-st parameter). You must use something like «cast(? as data-type-desired)». But it’s just for you info, since you try to use it here as a column name, which is not possible as described in 1).