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SQLite select where empty?
In SQLite, how can I select records where some_column is empty?
Empty counts as both NULL and "".
4 Answers
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When to use EntityManager.find() vs EntityManager.getReference() with JPA
... }
}
If i call find method, JPA provider, behind the scenes, will call
SELECT NAME, AGE FROM PERSON WHERE PERSON_ID = ?
UPDATE PERSON SET AGE = ? WHERE PERSON_ID = ?
If i call getReference method, JPA provider, behind the scenes, will call
UPDATE PERSON SET AGE = ? WHERE PERSON_ID = ?
And ...
How to fix Error: “Could not find schema information for the attribute/element” by creating schema
...tudio, open your app.config or web.config file.
Go to the "XML" menu and select "Create Schema". This action should create a new file called "app.xsd" or "web.xsd".
Save that file to your disk.
Go back to your app.config or web.config and in the edit window, right click and select properties. From...
How can I get column names from a table in Oracle?
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You can query the USER_TAB_COLUMNS table for table column metadata.
SELECT table_name, column_name, data_type, data_length
FROM USER_TAB_COLUMNS
WHERE table_name = 'MYTABLE'
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improve ...
Remove the cell highlight color of UITableView
I want to remove the default blue color of uitableview cell selection. I don't want any selection color there. I have not created a custom cell class. I'm customizing the cell by adding labels and buttons over it.
I tried doing:
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How to create P12 certificate for iOS distribution
...hain Access where it will be matched up with the private key. You can then select the cert, and open the arrow to also select the private key and export them together as a .p12 file from Keychain Access.
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How to drop all user tables?
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BEGIN
FOR cur_rec IN (SELECT object_name, object_type
FROM user_objects
WHERE object_type IN
('TABLE',
'VIEW',
'MATERIAL...
Problem with converting int to string in Linq to entities
...ode ends up looking like this:
var items = from c in contacts
select new ListItem
{
Value = SqlFunctions.StringConvert((double)c.ContactId).Trim(),
Text = c.Name
};
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How to get the top 10 values in postgresql?
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For this you can use limit
select *
from scores
order by score desc
limit 10
If performance is important (when is it not ;-) look for an index on score.
Starting with version 8.4, you can also use the standard (SQL:2008) fetch first
select *
from...
Dump a mysql database to a plaintext (CSV) backup from the command line
... separated) files which can import into Excel, etc, quite easily:
% echo 'SELECT * FROM table' | mysql -B -uxxx -pyyy database
Alternatively, if you've got direct access to the server's file system, use SELECT INTO OUTFILE which can generate real CSV files:
SELECT * INTO OUTFILE 'table.csv'
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