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Is a LINQ statement faster than a 'foreach' loop?
...by the simpler to understand code.
With other LINQ providers like LINQ-to-SQL, then since the query can filter at the server it should be much better than a flat foreach, but most likely you wouldn't have done a blanket "select * from foo" anyway, so that isn't necessarily a fair comparison.
Re PL...
When to prefer JSON over XML?
...
@sotn You haven't PL/SQL for JSON as have XML (e.g. XQuery). It's base for some NoSQL DB (eXist, MarkLogic Server, EMC Documentum xDB, BaseX, Zorba)
– Dmytro Melnychuk
Apr 23 '17 at 9:17
...
Does a UNIQUE constraint automatically create an INDEX on the field(s)?
...ail, user_id) is enough, you don't need a separate index on email only - MySQL can use leftmost parts of a composite index. There may be some border cases where the size of an index can slow down your queries, but you should not worry about them until you actually run into them.
As for testing inde...
MySql : Grant read only options?
...nts, and change it around to create a new user with similar privileges:
mysql> SHOW GRANTS FOR 'not_leet'@'localhost';
+------------------------------------------------------------------------------------------------------------------------------------+
| Grants for not_leet@localhost ...
Number of days between two dates in Joda-Time
...er compliant with JDBC 4.2 or later. No need for strings, no need for java.sql.* classes.
Where to obtain the java.time classes?
Java SE 8, Java SE 9, Java SE 10, and later
Built-in.
Part of the standard Java API with a bundled implementation.
Java 9 adds some minor features and fixes.
Java ...
Best design for a changelog / auditing database table? [closed]
...nd when?
So, in order to be able to answer such questions quickly (using SQL), we ended up having two additional columns in the audit table
object type (or table name)
object ID
That's when design of our audit log really stabilized (for a few years now).
Of course, the last "improvement" would...
Entity Framework - Code First - Can't Store List
... conversions may impact the ability of EF Core to translate expressions to SQL. A warning will be logged for such cases. Removal of these limitations is being considered for a future release." - Would still be nice though.
– Nicola Iarocci
May 8 at 8:34
...
Declare variable in table valued function
...
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Split code over multiple lines in an R script
...ong string where whitespace/structure is important to preserve (example: a SQL query using RODBC) there is a two step solution.
1) Bring the text string in across multiple lines
long_string <- "this
is
a
long
string
with
whitespace"
2) R will introduce a bunch of \n characters. Strip those...
What is the easiest way to ignore a JPA field during persistence?
...em with @Transient to exclude them from SELECT, INSERT, UPDATE, and DELETE SQL statements.
So, for basic attributes, you need to use @Transient in order to exclude a given property from being persisted.
For more details about computed entity attributes, check out this article.
Association...