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Change type of varchar field to integer: “cannot be cast automatically to type integer”
I have a small table and a certain field contains the type " character varying ". I'm trying to change it to " Integer " but it gives an error that casting is not possible.
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Is there a command like “watch” or “inotifywait” on the Mac?
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fswatch
fswatch is a small program using the Mac OS X FSEvents API to monitor a directory.
When an event about any change to that directory is received, the specified
shell command is executed by /bin/bash
If you're on GNU/Linux,
inotifywatch (par...
How to navigate through the source code by parts in CamelCase (instead of whole words)?
...for double-clicking can be restored by locating and disabling the setting called "Honor "CamelHumps" words settings when selecting on double click".
– Paul Lammertsma
Jan 22 '15 at 13:14
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Guava: Why is there no Lists.filter() function?
...er could be implemented as returning a new materialised list, which is actually what I would expect from a filter method for lists as opposed to the one on Iterable.
– Felix Leipold
May 27 '15 at 22:27
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Gradle - getting the latest release version of a dependency
...I've mistaken that with the plugin versions, cause for Maven 3 it does not allow RELEASE/LATEST anymore. But it's of course bad practice to use such version identifiers.
– khmarbaise
Apr 29 '12 at 14:26
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How do I map lists of nested objects with Dapper
... new {Ids = mappings.Select(m => m.LocationId).Distinct()}
);
Map it all up
Leaving this to the reader, you create a few maps and iterate through your courses populating with the locations.
Caveat the in trick will work if you have less than 2100 lookups (Sql Server), if you have more you p...
Maximum length of HTTP GET request
... using).
Most web servers have a limit of 8192 bytes (8 KB), which is usually configurable somewhere in the server configuration. As to the client side matter, the HTTP 1.1 specification even warns about this. Here's an extract of chapter 3.2.1:
Note: Servers ought to be cautious about dependi...
Select multiple columns in data.table by their numeric indices
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For versions of data.table >= 1.9.8, the following all just work:
library(data.table)
dt <- data.table(a = 1, b = 2, c = 3)
# select single column by index
dt[, 2]
# b
# 1: 2
# select multiple columns by index
dt[, 2:3]
# b c
# 1: 2 3
# select single column by na...
regex.test V.S. string.match to know if a string matches a regular expression
...sion
Use .test if you want a faster boolean check. Use .match to retrieve all matches when using the g global flag.
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What's wrong with foreign keys?
... get Orphaned Rows
you can get nice "on delete cascade" behavior, automatically cleaning up tables
knowing about the relationships between tables in the database helps the Optimizer plan your queries for most efficient execution, since it is able to get better estimates on join cardinality.
FKs giv...