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SQL WITH clause example [duplicate]
...me assigned to the sub-query is treated as though it was an inline view or table. The SQL WITH clause is basically a drop-in replacement to the normal sub-query.
Syntax For The SQL WITH Clause
The following is the syntax of the SQL WITH clause when using a single sub-query alias.
WITH <alias_n...
Discuz! X3 论坛标题字数突破80的限制 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...你的表的前缀，还有修改前一定要备份！！！）
ALTER TABLE `pre_forum_post` CHANGE `subject` `subject` varchar(255) NOT NULL;
ALTER TABLE `pre_forum_rsscache` CHANGE `subject` `subject` varchar(255) NOT NULL;
ALTER TABLE `pre_forum_thread` CHANGE `subject` `subject` varchar(255...
How do I put an already-running process under nohup?
... [-h] [jobspec ...]
Without options, each jobspec is removed from the table of active jobs. If the -h option is given, each jobspec is not
removed from the table, but is marked so that SIGHUP is not sent to the job if the shell receives a SIGHUP. If no jobspec is
present, and neither the -a...
Shortcuts in Objective-C to concatenate NSStrings
...ly as pleasant as just having a concatenation operator.
First, use an NSMutableString, which has an appendString method, removing some of the need for extra temp strings.
Second, use an NSArray to concatenate via the componentsJoinedByString method.
...
Is there an opposite to display:none?
...
When changing element's display in Javascript, in many cases a suitable option to 'undo' the result of element.style.display = "none" is element.style.display = "". This removes the display declaration from the style attribute, reverting the actual value of display property to the value set...
postgresql - replace all instances of a string within text field
...on:
replace(string text, from text, to text)
for instance :
UPDATE <table> SET <field> = replace(<field>, 'cat', 'dog')
Be aware, though, that this will be a string-to-string replacement, so 'category' will become 'dogegory'. the regexp_replace function may help you define a ...
Order Bars in ggplot2 bar graph
...y axis and the shortest bar would be furthest. So this is kind of like the Table I have
14 Answers
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How to get UITableView from UITableViewCell?
I have a UITableViewCell which is linked to an object and I need to tell if the cell is visible. From the research I've done, this means I need to somehow access the UITableView that contains it (from there, there are several ways to check if it's visible). So I'm wondering if UITableViewCell ...
Drop data frame columns by name
...multiple variables:
within(df, rm(x, y))
Or if you're dealing with data.tables (per How do you delete a column by name in data.table?):
dt[, x := NULL] # Deletes column x by reference instantly.
dt[, !"x"] # Selects all but x into a new data.table.
or for multiple variables
dt[, c("x","y...
Delimiters in MySQL
...* Inside the procedure, individual statements terminate with ; */
CREATE TABLE tablea (
col1 INT,
col2 INT
);
INSERT INTO tablea
SELECT * FROM table1;
CREATE TABLE tableb (
col1 INT,
col2 INT
);
INSERT INTO tableb
SELECT * FROM table2;
/* whole procedure ...