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How to drop all user tables?
...
BEGIN
FOR cur_rec IN (SELECT object_name, object_type
FROM user_objects
WHERE object_type IN
('TABLE',
'VIEW',
'MATERIAL...
Finding duplicate values in MySQL
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Do a SELECT with a GROUP BY clause. Let's say name is the column you want to find duplicates in:
SELECT name, COUNT(*) c FROM table GROUP BY name HAVING c > 1;
This will return a result with the name value in the first colum...
How do you join on the same table, twice, in mysql?
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you'd use another join, something along these lines:
SELECT toD.dom_url AS ToURL,
fromD.dom_url AS FromUrl,
rvw.*
FROM reviews AS rvw
LEFT JOIN domain AS toD
ON toD.Dom_ID = rvw.rev_dom_for
LEFT JOIN domain AS fromD
ON fromD.Dom_ID = rvw.rev_dom_from
ED...
How do you determine what SQL Tables have an identity column programmatically
...ct to change, version to version) is to use the
INFORMATION_SCHEMA views:
select COLUMN_NAME, TABLE_NAME
from INFORMATION_SCHEMA.COLUMNS
where COLUMNPROPERTY(object_id(TABLE_SCHEMA+'.'+TABLE_NAME), COLUMN_NAME, 'IsIdentity') = 1
order by TABLE_NAME
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Can an Option in a Select tag carry multiple values?
I got a select tag with some options in a HTML form:
(the data will be collected and processed using PHP)
15 Answers
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How do you do a limit query in JPQL or HQL?
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// SQL: SELECT * FROM table LIMIT start, maxRows;
Query q = session.createQuery("FROM table");
q.setFirstResult(start);
q.setMaxResults(maxRows);
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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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An explicit value for the identity column in table can only be specified when a column list is used
...tead of
SET IDENTITY_INSERT archive_table ON;
INSERT INTO archive_table
SELECT *
FROM source_table;
SET IDENTITY_INSERT archive_table OFF;
you need to write
SET IDENTITY_INSERT archive_table ON;
INSERT INTO archive_table (field1, field2, ...)
SELECT field1, field2, ...
FROM source_table;...
Intellij IDEA: Hotkey for “scroll from source”
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In the latest IntelliJ IDEA, there is a keymap entry called "Select in Project View" with no default shortcut. Just add a shortcut key to it. No need for a plugin.
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List of Timezone ID's for use with FindTimeZoneById() in C#?
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And if you'd like a HTML select with the Windows time zones in:
<select>
<option value="Morocco Standard Time">(GMT) Casablanca</option>
<option value="GMT Standard Time">(GMT) Greenwich Mean Time : Dublin, Edinburgh, Lisbon,...