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How to check for Is not Null And Is not Empty string in SQL server?
...ause. As NULL will evaluate as UNKNOWN for these rather than TRUE.
CREATE TABLE T
(
C VARCHAR(10)
);
INSERT INTO T
VALUES ('A'),
(''),
(' '),
(NULL);
SELECT *
FROM T
WHERE C <> ''
Returns just the single row A. I.e. The row...
How do I enumerate the properties of a JavaScript object? [duplicate]
...is needed and used because javascript conflates "Actor objects" with "Hash tables". when the object is a description of behaviors and traits, then the usual rules apply, you want to know about the properties on the object without concern for how they got there. If, on the other hand, your using th...
What is the use of hashCode in Java?
...hashCode() is used for bucketing in Hash implementations like HashMap, HashTable, HashSet, etc.
The value received from hashCode() is used as the bucket number for storing elements of the set/map. This bucket number is the address of the element inside the set/map.
When you do contains() it will t...
ActiveRecord.find(array_of_ids), preserving order
...
for me chaining don't work. Here tables name should be added before id:text like this: ["position((',' || somethings.id::text || ',') in ?)", ids.join(',') + ','] full version that worked for me: scope :for_ids_with_order, ->(ids) { order = sanitize_...
What is the difference between the remap, noremap, nnoremap and vnoremap mapping commands in Vim?
...wouldn't apply to (e.g. "insert").
Use help map-modes will show you a few tables that explain how to control which modes the mapping applies to.
Mode letters:
n: normal only
v: visual and select
o: operator-pending
x: visual only
s: select only
i: insert
c: command-line
l: insert, command-line, ...
C state-machine design [closed]
...I've no doubt there will be higher-level abstractions which may be more suitable nowadays but I suspect they'll all boil down to this same sort of structure.
And, as ldog states in a comment, you can avoid the globals altogether by passing a structure pointer to all functions (and using that in ...
DBMS_OUTPUT.PUT_LINE not printing
...(firstName, lastName) and then the other values from the select query in a table below.
6 Answers
...
What is “loose coupling?” Please provide examples
...imply modelled as dead data. in Database terms, all that is need here is a table CREATE TABLE entry (price INTEGER, quantity INTEGER)
– Jo So
Jul 9 '16 at 11:56
...
What is the best way to implement “remember me” for a website? [closed]
...and a token. The series and token are unguessable random numbers from a suitably large space. Both are stored together in a database table, the token is hashed (sha256 is fine).
When a non-logged-in user visits the site and presents a login cookie, the series identifier is looked up in the database....
What's the difference between session.persist() and session.save() in Hibernate?
... does not cascade to the child, i.e., only Parent is saved/inserted in the table. However, persist accomplished the task of saving both Parent and Child in one call. I am using a composite ID not a generated ID.
– arn-arn
Aug 11 '16 at 14:05
...