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postgresql return 0 if returned value is null
...al question).
There are two distinct "problems" here, the first is if a table or subquery has no rows, the second is if there are NULL values in the query.
For all versions I've tested, postgres and mysql will ignore all NULL values when averaging, and it will return NULL if there is nothing to ...
Store boolean value in SQLite
What is the type for a BOOL value in SQLite? I want to store in my table TRUE/FALSE values.
8 Answers
...
How do I update if exists, insert if not (AKA “upsert” or “merge”) in MySQL?
... @blub: If you create a unique key on geb and topic it will work (ALTER TABLE table ADD UNIQUE geb_by_topic (geb, topic)).
– chaos
Aug 2 '09 at 13:43
1
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Java GUI frameworks. What to choose? Swing, SWT, AWT, SwingX, JGoodies, JavaFX, Apache Pivot? [close
... components or very important features of UI components (like filtering on tables).
If SWT is missing a feature that you need, the framework is somewhat hostile to extending it. For example, you can't extend any class in it (the classes aren't final, they just throw exceptions when the package of t...
Repository Pattern Step by Step Explanation [closed]
...are persisted. All of the knowledge of persistence, including mapping from tables to objects, is safely contained in the repository.
Very often, you will find SQL queries scattered in the codebase and when you come to add a column to a table you have to search code files to try and find usages of a...
Objective-C categories in static library
...lass or category. While
this option will typically result in a
larger executable (due to additional
object code loaded into the
application), it will allow the
successful creation of effective
Objective-C static libraries that
contain categories on existing
classes.
and there is also recommendation...
How do I do a bulk insert in mySQL using node.js
...Ragnar123 led me to making this function:
function bulkInsert(connection, table, objectArray, callback) {
let keys = Object.keys(objectArray[0]);
let values = objectArray.map( obj => keys.map( key => obj[key]));
let sql = 'INSERT INTO ' + table + ' (' + keys.join(',') + ') VALUES ?';
...
Expand a div to fill the remaining width
...
This would be a good example of something that's trivial to do with tables and hard (if not impossible, at least in a cross-browser sense) to do with CSS.
If both the columns were fixed width, this would be easy.
If one of the columns was fixed width, this would be slightly harder but entir...
Get the week start date and week end date from week number
...ent: https://msdn.microsoft.com/en-us/library/ms181598.aspx
And here is a table that lays it out for you.
| DATEFIRST VALUE | Formula Value | 7 - DATEFIRSTVALUE - 1
Monday | 1 | 5 | 7 - 1- 1 = 5
Tuesday | 2 | 4 | ...
How to test an SQL Update statement before running it?
...man/5.0/en/commit.html
For example:
START TRANSACTION;
SELECT * FROM nicetable WHERE somthing=1;
UPDATE nicetable SET nicefield='VALUE' WHERE somthing=1;
SELECT * FROM nicetable WHERE somthing=1; #check
COMMIT;
# or if you want to reset changes
ROLLBACK;
SELECT * FROM nicetable WHERE somthing=1...