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What is the error “Every derived table must have its own alias” in MySQL?
...ich can the be used to refer to it in the rest of the outer query.
SELECT ID FROM (
SELECT ID, msisdn FROM (
SELECT * FROM TT2
) AS T
) AS T
In your case, of course, the entire query could be replaced with:
SELECT ID FROM TT2
...
Accessing Object Memory Address
...
The Python manual has this to say about id():
Return the "identity'' of an object.
This is an integer (or long integer)
which is guaranteed to be unique and
constant for this object during its
lifetime. Two objects with
non-overlapping lifetimes may h...
DISTINCT for only one column
... Server 2005 or above use this:
SELECT *
FROM (
SELECT ID,
Email,
ProductName,
ProductModel,
ROW_NUMBER() OVER(PARTITION BY Email ORDER BY ID DESC) rn
FROM Produ...
How do I find a default constraint using INFORMATION_SCHEMA?
...l_columns
INNER JOIN
sys.tables
ON all_columns.object_id = tables.object_id
INNER JOIN
sys.schemas
ON tables.schema_id = schemas.schema_id
INNER JOIN
sys.default_constraints
ON all_columns.default_object_id = default_constraints.object_...
Select last row in MySQL
...last of all the rows in the table, then this is finally the time where MAX(id) is the right answer! Kind of:
SELECT fields FROM table ORDER BY id DESC LIMIT 1;
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...
The JPA hashCode() / equals() dilemma
...Read this very nice article on the subject: Don't Let Hibernate Steal Your Identity.
The conclusion of the article goes like this:
Object identity is deceptively hard to implement correctly when
objects are persisted to a database. However, the problems stem
entirely from allowing objects t...
Delete multiple records using REST
...
Note that if considering DELETE and a body defining the resources to purge, that some intermediaries may not forward the body. Also, some HTTP clients cannot add a body to a DELETE. See stackoverflow.com/questions/299628/…
...
How to implement the activity stream in a social network
.... Structure so that you can quickly grab a batch of activities by activity ID or by using a set of friend IDs with time constraints.
Publish the activity IDs to Redis whenever an activity record is created, adding the ID to an "activity stream" list for every user who is a friend/subscriber that sho...
Defining a percentage width for a LinearLayout? [duplicate]
I want to define a percentage width (70%) for a LinearLayout that contains some buttons, so that I can center it and so that the child buttons can fill_parent. Here's a picture showing what I mean:
...
SQLAlchemy IN clause
...
How about
session.query(MyUserClass).filter(MyUserClass.id.in_((123,456))).all()
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 pa...