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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...
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...
differentiate null=True, blank=True in django
...e)
The database fields created for PostgreSQL 9.4 are :
CREATE TABLE Test (
id serial NOT NULL,
"charNull" character varying(10),
"charBlank" character varying(10) NOT NULL,
"charNullBlank" character varying(10),
"intNull" in...
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 ...
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 ?';
...
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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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...
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
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Relational Database Design Patterns? [closed]
...elationships using a foreign key.
Many-to-Many relationships with a bridge table.
Optional one-to-one relationships managed with NULLs in the FK column.
Star-Schema: Dimension and Fact, OLAP design.
Fully normalized OLTP design.
Multiple indexed search columns in a dimension.
"Lookup table" that con...
Auto increment primary key in SQL Server Management Studio 2012
How do I auto increment the primary key in a SQL Server database table, I've had a look through the forum but can't see how.
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