SQLAlchemy IN clause
sqlalchemy not in
sqlalchemy execute multiple statements
sqlalchemy query select specific columns
I'm trying to do this query in sqlalchemy
SELECT id, name FROM user WHERE id IN (123, 456)
I would like to bind the list
[123, 456] at execution time.
edit: Without the ORM, it would be
session.execute( select( [MyUserTable.c.id, MyUserTable.c.name], MyUserTable.c.id.in_((123, 456)) ) ).fetchall()
select() takes two parameters, the first one is a list of fields to retrieve, the second one is the
where condition. You can access all fields on a table object via the
Python, sqlalchemy, Select with WHERE IN clause, like() method itself produces the LIKE criteria for WHERE clause in the SELECT expression. result = session.query(Customers).filter An alternative way is using raw SQL mode with SQLAlchemy, I use SQLAlchemy 0.9.8, python 2.7, MySQL 5.X, and MySQL-Python as connector, in this case, a tuple is needed.
Assuming you use the declarative style (i.e. ORM classes), it is pretty easy:
query = db_session.query(User.id, User.name).filter(User.id.in_([123,456])) results = query.all()
db_session is your database session here, while
User is the ORM class with
__tablename__ equal to
SQLAlchemy ORM - Filter Operators, Return a literal clause, bound to a bind parameter. Literal clauses are created automatically when non- ClauseElement objects (such as strings, SQLAlchemy lets you just use strings, for those cases when the SQL is already known and there isn’t a strong need for the statement to support dynamic features. The text() construct is used to compose a textual statement that is passed to the database mostly unchanged. It constructs a new TextClause,
An alternative way is using raw SQL mode with SQLAlchemy, I use SQLAlchemy 0.9.8, python 2.7, MySQL 5.X, and MySQL-Python as connector, in this case, a tuple is needed. My code listed below:
id_list = [1, 2, 3, 4, 5] # in most case we have an integer list or set s = text('SELECT id, content FROM myTable WHERE id IN :id_list') conn = engine.connect() # get a mysql connection rs = conn.execute(s, id_list=tuple(id_list)).fetchall()
Hope everything works for you.
Column Elements and Expressions, Above, while the values method limited the VALUES clause to just two columns, the actual data we placed in values didn't get rendered into the SQLAlchemy Core - Using Conjunctions - Conjunctions are functions in SQLAlchemy module that implement relational operators used in WHERE clause of SQL expressions. The operators AND, OR, NOT, etc., a Home
With the expression API, which based on the comments is what this question is asking for, you can use the
in_ method of the relevant column.
SELECT id, name FROM user WHERE id in (123,456)
myList = [123, 456] select = sqlalchemy.sql.select([user_table.c.id, user_table.c.name], user_table.c.id.in_(myList)) result = conn.execute(select) for row in result: process(row)
This assumes that
conn have been defined appropriately.
SQL Expression Language Tutorial, For fine grained control over specific columns to count, to skip the usage of a subquery or otherwise control of the FROM clause, or to use other sq = session.query(RSID_Source).subquery() q = session.query(Genotypes).filter(Genotypes.rsid.in_(sq)) The issue is that in order to pass that list to SQLite (or any database, really), SQLAlchemy has to pass over each entry for your in clause as a variable. The SQL translates roughly to:
Just wanted to share my solution using sqlalchemy and pandas in python 3. Perhaps, one would find it useful.
import sqlalchemy as sa import pandas as pd engine = sa.create_engine("postgresql://postgres:my_password@my_host:my_port/my_db") values = [val1,val2,val3] query = sa.text(""" SELECT * FROM my_table WHERE col1 IN :values; """) query = query.bindparams(values=tuple(values)) df = pd.read_sql(query, engine)
Query API, ON clause is omitted, or if the ON clause is a plain SQL expression. an IN clause in order to locate related rows for multiple objects at once:. Sqlalchemy in_ subquery. I am trying to implement a select with a nested select clause, to find parents without any children. My tables (radically simplified) are as follows: select id from person where id not in (select person_id from foo);
Object Relational Tutorial, Embedding subqueries in an IN clause It is often useful in SQL to embed subqueries in an IN clause of another query. SQLAlchemy provides support for this as Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information. Learn more How to use NOT IN clause in sqlalchemy ORM query
What's New in SQLAlchemy 1.3?, How to select columns of different type in SQLAlchemy in the where clause? #4444. Closed. bobfang1992 opened this issue on Jan 14, 2019 · 3 comments. Note that SQLAlchemy’s clause constructs take operator precedence into account - so parenthesis might not be needed, for example, in an expression like x OR (y AND z) - AND takes precedence over OR. The base self_group() method of ClauseElement just returns self. class sqlalchemy.sql.expression.
Essential SQLAlchemy, So I know exactly the "desired" SQL to get the effect I want, but no idea how to express it "properly" in SQLAlchemy. Edit: in case it's important, I'm on SQLAlchemy 0.6.6. python sqlalchemy subquery
- I'm not currently using the ORM part of sqlachemy, but only SQL Expression API.
- Here is a link to the doc.
- If you use raw SQL for such simple queries you are better of using psycopg2 or other connector directly.
- I think you should do
args = [(tuple(ids_list),)], please double check.
- The OP is asking how to do this in sqlalchemy, not using raw dbapi call...
- This does not work with a single item list as it produces
(item, )and it's incorrect in SQL