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Set a DateTime database field to “Now”
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In SQL you need to use GETDATE():
UPDATE table SET date = GETDATE();
There is no NOW() function.
To answer your question:
In a large table, since the function is evaluated for each row, you will end up getting different values for the updated field.
So, if yo...
Storing Images in PostgreSQL
...ommend:
use blob (Binary Large OBject): for original image store, at your table. See Ivan's answer (no problem with backing up blobs!), PostgreSQL additional supplied modules, How-tos etc.
use a separate database with DBlink: for original image store, at another (unified/specialized) database. I...
Difference between single and double quotes in Bash
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The accepted answer is great. I am making a table that helps in quick comprehension of the topic. The explanation involves a simple variable a as well as an indexed array arr.
If we set
a=apple # a simple variable
arr=(apple) # an indexed array with a single e...
Why doesn't the height of a container element increase if it contains floated elements?
... you can use
.self_clear:after {
content: "";
clear: both;
display: table;
}
How Does CSS Float Work?
What is float exactly and what does it do?
The float property is misunderstood by most beginners. Well, what exactly does float do? Initially, the float property was introduced to flow...
Are PostgreSQL column names case-sensitive?
I have a db table say, persons in Postgres handed down by another team that has a column name say, "first_Name" . Now am trying to use PG commander to query this table on this column-name.
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What is the optimal algorithm for the game 2048?
...vidual rows and columns. A single row or column is a 16-bit quantity, so a table of size 65536 can encode transformations which operate on a single row or column. For example, moves are implemented as 4 lookups into a precomputed "move effect table" which describes how each move affects a single row...
How do I clone a Django model instance object and save it to the database?
...tion checking and depending on if they pass, i.e. the object is in another table that you are checking, you can set the new_instance.id = original_instance.id and save :) Thanks!
– radtek
Sep 25 '14 at 21:43
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Split delimited strings in a column and insert as new rows [duplicate]
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Here is another way of doing it..
df <- read.table(textConnection("1|a,b,c\n2|a,c\n3|b,d\n4|e,f"), header = F, sep = "|", stringsAsFactors = F)
df
## V1 V2
## 1 1 a,b,c
## 2 2 a,c
## 3 3 b,d
## 4 4 e,f
s <- strsplit(df$V2, split = ",")
data.frame(V1 ...
What are all possible pos tags of NLTK?
...abler if others are like me, I had wrong expectations. I expected a lookup table/list/map, mapping the pos acronyms like RB to their meaning like adverb. (Here is an example; or see @Suzana's answer, which links the Penn Treebank Tag Set). But you're right, the builtin nltk.help.upenn_tagset('RB')is...
Creating a jQuery object from a big HTML-string
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You can try something like below
$($.parseHTML(<<table html string variable here>>)).find("td:contains('<<some text to find>>')").first().prev().text();
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