Use this tag for questions about the psycopg3 Postgresql connector package for Python, a new implementation of the psycopg2 package.
psycopg3 is a new implementation of the psycopg2 Postgresql connector for Python.
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Questions tagged [psycopg3]
70 questions
25
votes
2 answers
ImportError "no pq wrapper available" when importing psycopg3
I installed pyscopg3 on my venv using pip install psycopg[binary] as per the documentation but I still get an import error:
Exception has occurred: ImportError
no pq wrapper available.
Attempts made:
- couldn't import psycopg 'c' implementation: No…
ericshaaan
- 251
- 1
- 3
- 5
11
votes
2 answers
Creating an SQLAlchemy engine based on psycopg3
I need to upgrade the following code to some equivalent code based on psycopg version 3:
import psycopg2
from sqlalchemy import create_engine
engine = create_engine('postgresql+psycopg2://', creator=connector)
This psycopg2 URL worked like a…
swiss_knight
- 5,787
- 8
- 50
- 92
7
votes
4 answers
How do I get libpq to be found by ctypes find_library?
I am building a simple DB interface in Python (3.9.9) and I am using psycopg (3.0.7) to connect to my Postgres (14.1) database. Until recently, the development of this app took place on Linux, but now I am using macOS Monterey on an M1 Mac mini.…
eslukas
- 245
- 2
- 8
5
votes
5 answers
Unable to import module 'lambda_function': No module named 'psycopg2._psycopg aws lambda function
I have installed the psycopg2 with this command in my package folder :
pip install --target ./package psycopg2 # Or
pip install -t ./package psycopg2
now psycopg2 module is in my package and I have created the zip and upload it in AWS lambda.
In my…
Jaskaran Singh
- 145
- 1
- 10
3
votes
2 answers
How to stop a PostgreSQL query if it runs longer than the some time limit with psycopg?
In Python is library psycopg and with that I can do queries.
I have an array with texts and I just iterate over them and run query to find this text in postgres. But some time the query takes so much time to execute and in that moment I want to…
Dmiich
- 325
- 2
- 16
3
votes
1 answer
Psycopg3: passing a list as parameter for IN statement using named arguments
How can I pass a list to an IN statement in a query using psycopg's named arguments?
Example:
cur.execute("""
SELECT name
FROM users
WHERE id IN (%(ids)s)
""",
{"ids": [1, 2, 3]})
When I do that, I get the…
Leonardo Freua
- 123
- 1
- 1
- 7
3
votes
1 answer
Return json/dictionary from psycopg3 SELECT query
I've been asked to migrate a program from psycopg2 to psycopg3. In this program they use
with connection.cursor(cursor_factory=RealDictCursor) as cursor:
to obtain a dictionary that's later turned into a JSON file.
My problem is that RealDictCursor…
neresi3
- 31
- 1
3
votes
3 answers
Copying CSV to PostgreSQL database using Psycopg3 in Python
I'm having a little difficulty understanding appropriate syntax for the psycopg3 library in Python. I'm trying to copy the contents of a .csv file into my database. The PostgreSQL documentation indicates copy should be written as follows:
COPY…
Caritas
- 45
- 3
2
votes
2 answers
Using a buffer to write a psycopg3 copy result through pandas
Using psycopg2, I could write large results as CSV using copy_expert and a BytesIO buffer like this with pandas:
copy_sql = "COPY (SELECT * FROM big_table) TO STDOUT CSV"
buffer = BytesIO()
cursor.copy_expert(copy_sql, buffer,…
FlipperPA
- 13,607
- 4
- 39
- 71
2
votes
0 answers
Should you share psycopg3 AsyncConnections between tasks in Python?
Psycopg3 supports async connections and async cursors. I have multiple writer tasks writing to a database. Should I pass each of those tasks the same AsyncConnection? If not, should I pass them the same AsyncCursor? Or should I make a new connection…
Justin Calareso
- 61
- 8
2
votes
1 answer
copying a table across servers with psycopg3
I'm working from and example in the psycopg3 documentation to copy a table from one database to another: link
dsn_src = 'postgresql:///dev_db'
dsn_tgt = 'postgresql:///prod_test'
with psycopg.connect(dsn_src) as conn1, psycopg.connect(dsn_tgt) as…
user1290426
- 153
- 3
- 7
2
votes
0 answers
Psycopg3 won't install on CentOS
I'm having issues installing Psycopg3 in a Docker image with python 3.7.3, pip 22.0.4 and CentOS Linux release 7.8.2003 (Core).
When I run pip install psycopg[binary] I get the following messages and errors:
Collecting psycopg[binary]
Downloading…
Dula
- 1,404
- 1
- 14
- 29
2
votes
2 answers
Mashed-up emojis stored in a Postgres database not returned as single emoji using Python 3.9 with psycopg3. For example returned \u200d
I am reading text containing emojis from a Postgres 13 database. Turns out that my Python/psycopg query does not decode/return the text as I would expect.
Via Postgres psql client
Within postgres:13 container
select description from profile WHERE…
smile2day
- 1,585
- 1
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- 34
2
votes
1 answer
How to create a database using psycopg3?
This does not work:
conn = psycopg.connect(dsn)
conn.execute("CREATE DATABASE test")
Here is the documentation about transactions in psycopg3: https://www.psycopg.org/psycopg3/docs/basic/transactions.html
The most important statement for this…
nagylzs
- 3,954
- 6
- 39
- 70
1
vote
1 answer
Passing nested tuple to VALUES in psycopg3
I'm trying to updates some psycopg2 code to psycopg3. I'm trying to do a selection based on a set of values passed from Python (joining with an existing table). Without the join, a simplified example is:
with connection.cursor() as cur:
sql =…
xioxox
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- 1
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