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How do I modify fields inside the new PostgreSQL JSON datatype?
With postgresql 9.3 I can SELECT specific fields of a JSON data type, but how do you modify them using UPDATE? I can't find any examples of this in the postgresql documentation, or anywhere online. I have tried the obvious:
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Iterate through options
I have a <select> element in HTML. This element represents a drop down list. I'm trying to understand how to iterate through the options in the <select> element via JQuery.
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How to change options of with jQuery?
Suppose a list of options is available, how do you update the <select> with new <option> s?
9 Answers
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Using awk to print all columns from the nth to the last
... You can also use "-b" to specify the position (from the Nth character onwards).
– Dakatine
Sep 10 '13 at 13:56
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delete vs delete[] operators in C++
... I wonder if using delete on a new[] array of primitive types like int or char (no constructor/destructor) necessarily leads to undefined behavior, too. It seems the array size isn't stored anywhere when using primitive types.
– thomiel
Jul 6 '14 at 11:16
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using href links inside tag
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<select name="forma" onchange="location = this.value;">
<option value="Home.php">Home</option>
<option value="Contact.php">Contact</option>
<option value="Sitemap.php">Sitemap</option>...
Difference between VARCHAR and TEXT in MySQL [duplicate]
When we create a table in MySQL with a VARCHAR column, we have to set the length for it. But for TEXT type we don't have to provide the length.
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MySQL: Set user variable from result of query
...need to move the variable assignment into the query:
SET @user := 123456;
SELECT @group := `group` FROM user WHERE user = @user;
SELECT * FROM user WHERE `group` = @group;
Test case:
CREATE TABLE user (`user` int, `group` int);
INSERT INTO user VALUES (123456, 5);
INSERT INTO user VALUES (111111...
How to read a local text file?
...tion that takes in the file’s path and converts each line of text into a char array, but it’s not working.
20 Answers
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Why use the INCLUDE clause when creating an index?
...ot in the WHERE/JOIN/GROUP BY/ORDER BY, but only in the column list in the SELECT clause.
The INCLUDE clause adds the data at the lowest/leaf level, rather than in the index tree.
This makes the index smaller because it's not part of the tree
INCLUDE columns are not key columns in the index, so th...