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What is PostgreSQL explain telling me exactly?
...ly 1 sentence of technical content: "• EXPLAIN works on any DML not just SELECT (ie UPDATE, DELETE, and INSERT)". My biggest misunderstanding is what "startup" time means, and that's not explained anywhere in these ~30 slides.
– Mark E. Haase
Feb 19 '16 at 15...
What is cardinality in MySQL?
...ow cardinality column with only 2 possible values as the index will not be selective enough to be used.
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Best way to organize jQuery/JavaScript code (2013) [closed]
... var parent = "";
if(selected_folder != "" ){
parent = selected_folder+" .content";
}
$R.find(".layer").clone()
.addClass(name).html(...
Adding a library/JAR to an Eclipse Android project
...w application project.
When you are creating the library project, you can select any application name, package, and set other fields as needed, as shown in figure 1.
Next, set the project's properties to indicate that it is a library project:
In the Package Explorer, right-click the library proje...
Android Gallery on Android 4.4 (KitKat) returns different URI for Intent.ACTION_GET_CONTENT
...tyForResult(Intent.createChooser(intent, getResources().getString(R.string.select_picture)),GALLERY_INTENT_CALLED);
} else {
Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
intent.addCategory(Intent.CATEGORY_OPENABLE);
intent.setType("image/jpeg");
startActivityForResult(int...
In Eclipse, what can cause Package Explorer “red-x” error-icon when all Java sources compile without
...ers e.g __duplicatefile.java . To fix this, rightclick on the project and select : Show In > Navigator . Then delete the duplicate files with underscore and build your project.
– GraSim
May 29 '15 at 10:28
...
How do I find a default constraint using INFORMATION_SCHEMA?
...our constraints!)
-- returns name of a column's default value constraint
SELECT
default_constraints.name
FROM
sys.all_columns
INNER JOIN
sys.tables
ON all_columns.object_id = tables.object_id
INNER JOIN
sys.schemas
ON tables.schema_id = schemas.s...
Search text in stored procedure in SQL Server
...t the schema name by adding SCHEMA_NAME(o.schema_id) AS Schema_Name to the select clause.
– patricus
Jul 7 '16 at 15:07
6
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What is Func, how and when is it used
...ied to any particular functionality.
For example, consider the Enumerable.Select extension method.
The pattern is: for every item in a sequence, select some value from that item (e.g., a property) and create a new sequence consisting of these values.
The placeholder is: some selector function tha...
Postgresql query between date ranges
... things become simpler if you use >= start AND < end.
For example:
SELECT
user_id
FROM
user_logs
WHERE
login_date >= '2014-02-01'
AND login_date < '2014-03-01'
In this case you still need to calculate the start date of the month you need, but that should be straight forw...