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What, exactly, is needed for “margin: 0 auto;” to work?
...y head:
The element must be block-level, e.g. display: block or display: table
The element must not float
The element must not have a fixed or absolute position1
Off the top of other people's heads:
The element must have a width that is not auto2
Note that all of these conditions must be tru...
Why should I use document based database instead of relational database?
...ds of applications or domains where the document based database is more suitable than the relational database?
7 Answers
...
How do we count rows using older versions of Hibernate (~2009)?
For example, if we have a table Books, how would we count total number of book records with hibernate?
8 Answers
...
how to display full stored procedure code?
...
just in case anyone is confused as to where that table is: pg_catalog -> system table -> pg_proc
– Dimitris
Aug 24 '12 at 7:19
...
What is the difference between single and double quotes in SQL?
...stant or a date/time constant.
Double quotes delimit identifiers for e.g. table names or column names. This is generally only necessary when your identifier doesn't fit the rules for simple identifiers.
See also:
Do different databases use different name quote?
You can make MySQL use double-q...
How can I remove the search bar and footer added by the jQuery DataTables plugin?
I am using jQuery DataTables .
18 Answers
18
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How to select rows from a DataFrame based on column values?
... links could be very useful to many of you: pandas.pydata.org/pandas-docs/stable/indexing.html gregreda.com/2013/10/26/working-with-pandas-dataframes
– tremendows
May 27 '14 at 7:32
...
What is the use of the square brackets [] in sql statements?
... You may also define a column name called select but select select from mytable would throw an error so select [select] from mytable would make it a valid query. Whatever word becomes colourful in your SQL management studio, should be surrounded by brackets if you want to use them as column / table...
Extract a substring according to a pattern
...sapply(strsplit(string, ":"), "[", 2)
## [1] "E001" "E002" "E003"
3) read.table
read.table(text = string, sep = ":", as.is = TRUE)$V2
## [1] "E001" "E002" "E003"
4) substring
This assumes second portion always starts at 4th character (which is the case in the example in the question):
substring(st...
Using margin:auto to vertically-align a div
...he three elements have to be nested like so:
.container {
display: table;
height: 100%;
position: absolute;
overflow: hidden;
width: 100%;
}
.helper {
#position: absolute;
#top: 50%;
display: table-cell;
vertical-align: middle;
}
.content {
#position: rela...