大约有 40,000 项符合查询结果（耗时：0.0396秒） [XML]
INSERT IF NOT EXISTS ELSE UPDATE?
...ike:
insert or replace into Book (ID, Name, TypeID, Level, Seen) values
((select ID from Book where Name = "SearchName"), "SearchName", ...);
Note that any field not in the insert list will be set to NULL if the row already exists in the table. This is why there's a subselect for the ID column: I...
PostgreSQL: How to pass parameters from command line?
...3="'2010-11-12'"
and then refer to the variables in sql as :v1, :v2 etc
select * from table_1 where id = :v1;
Please pay attention on how we pass string/date value using two quotes " '...' "
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Selecting/excluding sets of columns in pandas [duplicate]
...e to create views or dataframes from an existing dataframe based on column selections.
9 Answers
...
What is the best way to paginate results in SQL Server
... sake of this example, let's assume that the query you're dealing with is
SELECT * FROM Orders WHERE OrderDate >= '1980-01-01' ORDER BY OrderDate
In this case, you would determine the total number of results using:
SELECT COUNT(*) FROM Orders WHERE OrderDate >= '1980-01-01'
...which may ...
Generate GUID in MySQL for existing Data?
...e BEFORE UPDATE on YourTable
FOR EACH ROW
BEGIN
SET new.guid_column := (SELECT UUID());
END
//
Then execute
UPDATE YourTable set guid_column = (SELECT UUID());
And DROP TRIGGER beforeYourTableUpdate;
UPDATE
Another solution that doesn't use triggers, but requires primary key or unique inde...
oracle top 替代方案 - 数据库(内核) - 清泛网 - 专注C/C++及内核技术
oracle top 替代方案由于Oracle不支持select top 语句，所以在Oracle中经常是用order by 跟 rownum的组合来实现select top n的查询。select * from (...由于Oracle不支持select top 语句，所以在Oracle中经常是用order by 跟 rownum 的组合来实现select top n的查...
How to get size of mysql database?
...
Run this query and you'll probably get what you're looking for:
SELECT table_schema "DB Name",
ROUND(SUM(data_length + index_length) / 1024 / 1024, 1) "DB Size in MB"
FROM information_schema.tables
GROUP BY table_schema;
This query comes from the mysql forums, where there are...
What must I know to use GNU Screen properly? [closed]
... target window. Warning: it will let you know if anything changes.
Want to select window 15 directly? Try these in your .screenrc file:
bind ! select 11
bind @ select 12
bind \# select 13
bind $ select 14
bind % select 15
bind \^ select 16
bind & select 17
bind * select 18
bind ( selec...
Getting back old copy paste behaviour in tmux, with mouse
... -g mode-mouse off
set-option -g mouse-resize-pane off
set-option -g mouse-select-pane off
set-option -g mouse-select-window off
# toggle mouse mode to allow mouse copy/paste
# set mouse on with prefix m
bind m \
set -g mode-mouse on \;\
set -g mouse-resize-pane on \;\
set -g mouse-selec...
Escape Character in SQL Server
...s the second answer shows it's possible to escape single quote like this:
select 'it''s escaped'
result will be
it's escaped
If you're concatenating SQL into a VARCHAR to execute (i.e. dynamic SQL), then I'd recommend parameterising the SQL. This has the benefit of helping guard against SQL in...