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What are the use cases for selecting CHAR over VARCHAR in SQL?
...rchar, it's free to use 1-3 bytes per character as needed. This is in the MySQL manual: dev.mysql.com/doc/refman/5.0/en/charset-unicode-utf8.html
– Gavin Towey
Mar 27 '14 at 2:14
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PostgreSQL: Modify OWNER on all tables simultaneously in PostgreSQL
...functions as the signature is part of the function name. Granted, I have a MySQL background and am not that familiar with Postgres.
However, pg_dump allows you to dump just the schema and this contains the ALTER xxx OWNER TO yyy; statements you need. Here is my bit of shell magic on the topic
pg_d...
On delete cascade with doctrine2
...rine's cascade={"remove"} removes the related entities before removing the root entity (it has to). So when the root entity is deleted there aren't any foreign relations left for onDelete="CASCADE" to delete. But to be sure I would suggest you simply create a small test case and look at the queries ...
Getting root permissions on a file inside of vi? [closed]
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If you need root privileges to save a new file, replace % with the name (including path) of the new file.
– gvkv
Aug 10 '10 at 0:47
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How to select all records from one table that do not exist in another table?
...E b.Key IS NULL;
https://www.cloudways.com/blog/how-to-join-two-tables-mysql/
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Verify a certificate chain using openssl verify
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If a certificate is found which is its own issuer it is assumed to be the root CA.
In other words, root CA needs to self signed for verify to work. This is why your second command didn't work. Try this instead:
openssl verify -CAfile RootCert.pem -untrusted Intermediate.pem UserCert.pem
It will v...
How to serialize an object to XML without getting xmlns=“…”?
...ter, object, xmlns);
you will have the three namespaces declared in the root element and no more needed to be generated in the other elements which will be prefixed accordingly
<root xmlns:one="urn:names:specification:schema:xsd:one" ... />
<one:Element />
<two:ElementFromAn...
When to use inline function and when not to use it?
... most important rule of optimization is that premature optimization is the root of all evil. Always write clear code (using efficient algorithms), then profile your program and only optimize functions that are taking too long.
If you find a particular function is very short and simple, and it's ge...
ActiveRecord.find(array_of_ids), preserving order
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The answer is for mysql only
There is a function in mysql called FIELD()
Here is how you could use it in .find():
>> ids = [100, 1, 6]
=> [100, 1, 6]
>> WordDocument.find(ids).collect(&:id)
=> [1, 6, 100]
>> WordD...
Mac SQLite editor [closed]
I am aware of CocoaMySQL but I have not seen a Mac GUI for SQLite, is there one?
15 Answers
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