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Oracle: If Table Exists
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declare
c int;
begin
select count(*) into c from user_tables where table_name = upper('table_name');
if c = 1 then
execute immediate 'drop table table_name';
end if;
end;
That's for checking whether a table in the current schema exi...
Find CRLF in Notepad++
...h processes:
Simple search (Ctrl+F), Search Mode = Normal
You can select an EOL in the editing window.
Just move the cursor to the end of the line, and type Shift+Right Arrow.
or, to select EOL with the mouse, start just at the line end and drag to the start of the next line; dr...
Calculate difference between two datetimes in MySQL
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USE TIMESTAMPDIFF MySQL function. For example, you can use:
SELECT TIMESTAMPDIFF(SECOND, '2012-06-06 13:13:55', '2012-06-06 15:20:18')
In your case, the third parameter of TIMSTAMPDIFF function would be the current login time (NOW()). Second parameter would be the last login time, w...
How do I create test and train samples from one dataframe with pandas?
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scikit learn's train_test_split is a good one.
from sklearn.model_selection import train_test_split
train, test = train_test_split(df, test_size=0.2)
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Using IQueryable with Linq
...ram. Your program then filters the data. In essence, the database does a SELECT * FROM Products, and returns EVERY product to you.
With the right IQueryable<T> provider, on the other hand, you can do:
IQueryable<Product> products = myORM.GetQueryableProducts();
var productsOver25 =...
How do I turn off Oracle password expiration?
...rtain user profile in Oracle first check which profile the user is using:
select profile from DBA_USERS where username = '<username>';
Then you can change the limit to never expire using:
alter profile <profile_name> limit password_life_time UNLIMITED;
If you want to previously che...
How to deselect a selected UITableView cell?
I am working on a project on which I have to preselect a particular cell.
24 Answers
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Transferring an app to another Firebase account
...another account. All you have to do is:
Go to your Firebase console, and select the project you want to shift.
Select the cog icon besides the project name on top right.
Select Permissions from the flyout.
Select Advanced permission settings hyperlink.
You've reached the IAM & Admin page of Fi...
Spring JPA selecting specific columns
...Spring JPA to perform all database operations. However I don't know how to select specific columns from a table in Spring JPA?
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SQL Server: Filter output of sp_who2
... SPID_1 INT,
REQUESTID INT
)
INSERT INTO @Table EXEC sp_who2
SELECT *
FROM @Table
WHERE ....
And filter on what you require.
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