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How to round an average to 2 decimal places in PostgreSQL?
...old syntax for casting,
SELECT ROUND(AVG(some_column)::numeric,2)
FROM table;
works with any version of PostgreSQL.
There are a lack of overloads in some PostgreSQL functions, why (???): I think "it is a lack" (!), but @CraigRinger, @Catcall and the PostgreSQL team agree about "pg's historic r...
.NET HashTable Vs Dictionary - Can the Dictionary be as fast?
I am trying to figure out when and why to use a Dictionary or a HashTable. I have done a bit of a search on here and have found people talking about the generic advantages of the Dictionary which I totally agree with, which leads the boxing and unboxing advantage for a slight performance gain.
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What datatype to use when storing latitude and longitude data in SQL databases? [duplicate]
... those fields in mysql to benefit from the fact they are integers:
Create Table: CREATE TABLE `Locations` (
`lat` int(10) unsigned NOT NULL,
`lon` int(10) unsigned NOT NULL,
`location` text,
PRIMARY KEY (`lat`,`lon`) USING BTREE,
KEY `index_location` (`locationText`(30))
) ENGINE=InnoDB D...
Which one is the best PDF-API for PHP? [closed]
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mpdf unfortunately doesn't seem to handle large table cells well. As soon as the content exceeds a page, it starts to scale down, which makes it useless for any project that has big tables. Apart from that; it's easy to use, performant, and well documented.
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Convert text into number in MySQL query
... field,CONVERT(SUBSTRING_INDEX(field,'-',-1),UNSIGNED INTEGER) AS num
FROM table
ORDER BY num;
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Does opacity:0 have exactly the same effect as visibility:hidden
...s* No No
display: none Yes No No
* Yes inside a table element, otherwise No.
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Convert a matrix to a 1 dimensional array
...dimensions of the matrix/array.
Elts_int <- as.matrix(tmp_int) # read.table returns a data.frame as Brandon noted
dim(Elts_int) <- (maxrow_int*maxcol_int,1)
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Can I use GDB to debug a running process?
...so use the "file" command
to specify the program, and to load its symbol table.
NOTE: You may have difficulty attaching to a process due to improved security in the Linux kernel - for example attaching to the child of one shell from another.
You'll likely need to set /proc/sys/kernel/yama/ptr...
setting multiple column using one update
How to set multiple columns of a table using update query in mysql?
2 Answers
2
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How to get next/previous record in MySQL?
...ded the results ordered by date since I can't rely on the ID field as a sortable column. Here's the solution I came up with.
First we find out the index of the desired record in the table, when it's sorted as we want:
SELECT row
FROM
(SELECT @rownum:=@rownum+1 row, a.*
FROM articles a, (SELECT @...