I want to create a UDF that contains parameterized query. Since I want to reuse this function, I also want to parameterize the table name. Is this possible in Snowflake Data Warehouse(or Oracle since it's bit similar in terms of syntax)?
I don't think this can be done using only SQL. Any input on how it can be achieved using Python?
You can't use a table name as a bind variable in Oracle. The query is parsed at compile time, not run time. You have to use EXECUTE IMMEDIATE
or dbms_sql
.
This is a really basic programming question, and not really related to Snowflake. So you should have investigated more before asking here. But here's a sketch of an answer for you:
#!/usr/bin/env python
# Connect to Snowflake
# See https://docs.snowflake.net/manuals/user-guide/python-connector-example.html#connecting-
...
con =
...
# Scan the file to build the table/column info
tables = {}
with open("zz.csv") as f:
for l in f.readlines():
tname, cname = l.split(",")
tables.setdefault(tname.strip(), []).append(cname.strip())
# Run a query for each query
for tname, clist in tables.iteritems():
query = """select {columns} from {table}
group by {columns}
having count(*) > 1
""".format(columns=",".join(clist), table=tname)
print("Running query: {0}".format(query))
cur = con.cursor()
cur.execute(query)
for rec in cur:
print("DUPLICATED RECORD: {0}".format(rec))
@MarcinZukowski Thanks for info. Yes I checked it and they are planning to launch it in June. I just have query to validate PK constraint in the UDF which doesn't need to be in UDF. My CSV looks like this which has table name and its primary keys:
| Table Name | Primary Key | | Table 1 | Col1 | | Table 1 | Col2 | | Table 1 | Col3 | | Table 2 | Col11 | | Table 2 | Col12 |
I want to execute below query for every table from this CSV. Here table name can be single argument but column names will have to be varying since tables can 1 or more primary keys.
select Col1, Col2, Col3 from Table1
group by Col1, Col2, Col3
having count(*)>1
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