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MySQL select with CONCAT condition
I'm trying to compile this in my mind.. i have a table with firstname and lastname fields
and i have a string like "Bob Jones" or "Bob Michael Jones" and several others.
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Assigning default value while creating migration file
... t.boolean :active, :default => 1 in migration file for creating entire table. After ran that migration when i checked in db it made as null. Even though i told default as "1". After that slightly i changed migration file like this then it worked for me for setting default value on create table m...
PostgreSQL return result set as JSON array?
...scribes how to generate a JSON object, with each key being a column in the table and each value being an array of the values of the column. It's the result that looks like this:
{"a":[1,2,3], "b":["value1","value2","value3"]}
9.5 and up
We can leverage the json_build_object function:
SELECT
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Showing data values on stacked bar chart in ggplot2
... Thanks for this answer. I used it to do similar using data.table instead of plyr, so something like this: Data.dt[,list(Category, Frequency, pos=cumsum(Frequency)-0.5*Frequency), by=Year]
– atomicules
May 17 '12 at 15:49
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disable all form elements inside div
... function below at various points. Works in a div or button elements in a table as long as the right selector is used. Just ":button" would not re-enable for me.
function ToggleMenuButtons(bActivate) {
if (bActivate == true) {
$("#SelectorId :input[type='button']").prop("disabled", tru...
How do I convert an interval into a number of hours with postgres?
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If you convert table field:
Define the field so it contains seconds:
CREATE TABLE IF NOT EXISTS test (
...
field INTERVAL SECOND(0)
);
Extract the value. Remember to cast to int other wise you can get an unpleasant su...
Convert a string to int using sql query
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You could use CAST or CONVERT:
SELECT CAST(MyVarcharCol AS INT) FROM Table
SELECT CONVERT(INT, MyVarcharCol) FROM Table
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What's the most efficient way to erase duplicates and sort a vector?
...or first before it will work as you intend.
std::unique is defined to be stable, so the vector will still be sorted after running unique on it.
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Difference between sh and bash
.../sh could be a symbolic link or a hard link.
If it's a symbolic link, a portable way to resolve it is:
% file -h /bin/sh
/bin/sh: symbolic link to bash
If it's a hard link, try
% find -L /bin -samefile /bin/sh
/bin/sh
/bin/bash
In fact, the -L flag covers both symlinks and hardlinks,
but the d...
When to use a Content Provider
... best thing about it is that you can customize the contentproviders for suitable URIs.
Here's a scenario where you may have 5 tables in your database, but you need to join a few of them in certain orders before using them. And make a content URI for each of these joins. You could then each use thes...