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Equals(=) vs. LIKE
... these operators!
= is a comparison operator that operates on numbers and strings. When comparing strings, the comparison operator compares whole strings.
LIKE is a string operator that compares character by character.
To complicate matters, both operators use a collation which can have important...
Are there disadvantages to using a generic varchar(255) for all text-based fields?
... (If you're wondering, it's this way because Ruby on Rails migrations map String fields to VARCHAR(255) by default and I never bothered to override it).
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How to persist a property of type List in JPA?
... should anyone be looking for an alternative solution where you store your string lists as one field in your database, here's how I solved that. Create a Converter like this:
import java.util.Arrays;
import java.util.List;
import javax.persistence.AttributeConverter;
import javax.persistence.Conve...
Resolve build errors due to circular dependency amongst classes
...o handle the forward declarations. The only "disadvantage" would be in the extra files. I assume you always include a.fwd.h in a.h, to assure they stay in sync. The example code is missing where these classes are used. a.h and b.h will both need to be included since they won't function in isolatio...
How to connect android emulator to the internet
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I've created a simple script to do just that, you can check it out at: gist.github.com/brotoo25/246d8767982ed74ce98ed165ea099a5d
– Brotoo25
Apr 26 '19 at 23:24
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What are the differences between LDAP and Active Directory?
...ectory Access Protocol, LDAP, is developed. It uses the TCP/IP stack and a string encoding scheme of the X.500 Directory Access Protocol (DAP), giving it more relevance on the Internet.
Lastly, based on this LDAP/X.500 stack, Microsoft implemented a modern directory service for Windows, originating...
Group query results by month and year in postgresql
...ht make sense to use date_trunc, but in some cases having a formatted date string is preferable, and if you're using a performant data warehouse the additional computation might not be a deal breaker. For example, if you are running a quick analytics report using redshift, and it usually takes 3 sec...
Dealing with nginx 400 “The plain HTTP request was sent to HTTPS port” error
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Doesn't seem to work with multiple conf files. Says there are 2 duplicate defaults. Use Alexander's solution.
– Ryall
May 7 '16 at 21:54
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How to change the CHARACTER SET (and COLLATION) throughout a database?
...DEFAULT is not null, CONCAT(' DEFAULT \'', COLUMN_DEFAULT, '\''), ''), if (EXTRA != '', CONCAT(' ', EXTRA), '')))), ';') as alter_statement
FROM information_schema.columns a
INNER JOIN INFORMATION_SCHEMA.TABLES b ON a.TABLE_CATALOG = b.TABLE_CATALOG
AND a.TABLE_SCHEMA = b.TABLE_SCHEM...
Why can Java Collections not directly store Primitives types?
...tion of primitives. Even in the few cases where I might have wanted to the extra time and space costs of using the reference objects has been negligible. In particular I find that many people think they want Map<int,T>, forgetting that an array will do that trick very nicely.
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