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Easiest way to copy a table from one database to another?
What is the best method to copy the data from a table in one database to a table in another database when the databases are under different users?
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SQLite select where empty?
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It looks like you can simply do:
SELECT * FROM your_table WHERE some_column IS NULL OR some_column = '';
Test case:
CREATE TABLE your_table (id int, some_column varchar(10));
INSERT INTO your_table VALUES (1, NULL);
INSERT INTO your_table VALUES (2, '');
INSERT INTO your_t...
中文网（自研/维护）拓展 · App Inventor 2 中文网
...otherwise.
DatabasePath()
Returns the path to the database.
Delete(table,whereClause,bindParams)
Executes a SQL DELETE statement.
DeleteAsync(tag,table,whereClause,bindParams)
Executes a SQL DELETE statement, asynchronously.
DeleteDatabase()
Delete the database.
Execute(sql,bi...
MySQL: Quick breakdown of the types of joins [duplicate]
...oin type
JOIN: Return rows when there is at least one match in both tables
LEFT JOIN: Return all rows from the left table, even if there are no matches in the right table
RIGHT JOIN: Return all rows from the right table, even if there are no matches in the left table
FULL JOIN: Return r...
How to create ENUM type in SQLite?
I need to convert a table from MySQL to SQLite, but I can't figure out how to convert an enum field, because I can't find ENUM type in SQLite.
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How to import multiple .csv files at once?
...r answers using things like do.call(rbind,...), dplyr::bind_rows() or data.table::rbindlist().
If you really want each data frame in a separate object, even though that's often inadvisable, you could do the following with assign:
temp = list.files(pattern="*.csv")
for (i in 1:length(temp)) assign(...
How to center an element horizontally and vertically
...y/horizontally centered!</span>
</div>
Approach 3 - table-cell/vertical-align: middle:
Example Here / Full Screen Example
In some cases, you will need to ensure that the html/body element's height is set to 100%.
For vertical alignment, set the parent element's width/height...
SELECT INTO a table variable in T-SQL
... a complex SELECT query, from which I would like to insert all rows into a table variable, but T-SQL doesn't allow it.
8 An...
How to get database structure in MySQL via query
Is it possible to somehow get structure of MySQL database, or just some table with simple query?
10 Answers
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Simple basic explanation of a Distributed Hash Table (DHT)
...tore a particular key is found by hashing that key, so in effect your hash-table buckets are now independent nodes in a network.
This gives a lot of fault-tolerance and reliability, and possibly some performance benefit, but it also throws up a lot of headaches. For example, what happens when a nod...