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mysql update column with value from another table
...
Second possibility is,
UPDATE TableB
SET TableB.value = (
SELECT TableA.value
FROM TableA
WHERE TableA.name = TableB.name
);
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How to see full query from SHOW PROCESSLIST
... pull the data and look at 'INFO' column which contains the whole query :
select * from INFORMATION_SCHEMA.PROCESSLIST where db = 'somedb';
You can add any condition or ignore based on your requirement.
The output of the query is resulted as :
+-------+------+-----------------+--------+--------...
How can I copy the output of a command directly into my clipboard?
...mewhere else other than a X application, try this one:
cat file | xclip -selection clipboard
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LINQ - Full Outer Join
...rst.ID equals last.ID into temp
from last in temp.DefaultIfEmpty()
select new
{
first.ID,
FirstName = first.Name,
LastName = last?.Name,
};
var rightOuterJoin =
from last in lastNames
join first in firstNames on last.ID equals first.ID into temp
fr...
Correct use of Multimapping in Dapper
...
I just ran a test that works fine:
var sql = "select cast(1 as decimal) ProductId, 'a' ProductName, 'x' AccountOpened, cast(1 as decimal) CustomerId, 'name' CustomerName";
var item = connection.Query<ProductItem, Customer, ProductItem>(sql,
(p, c) => { p.Cu...
Select Pandas rows based on list index
...
For large datasets, it is memory efficient to read only selected rows via the skiprows parameter.
Example
pred = lambda x: x not in [1, 3]
pd.read_csv("data.csv", skiprows=pred, index_col=0, names=...)
This will now return a DataFrame from a file that skips all rows except 1 and ...
How to set selected item of Spinner by value, not by position?
I have a update view, where I need to preselect the value stored in database for a Spinner.
25 Answers
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What's the recommended way to connect to MySQL from Go?
...l", store.user+":"+store.password+"@/"+store.database)
defer con.Close()
Select one row :
row := con.QueryRow("select mdpr, x, y, z from sometable where id=?", id)
cb := new(SomeThing)
err := row.Scan(&cb.Mdpr, &cb.X, &cb.Y, &cb.Z)
Select multiple rows and build an array with re...
efficient way to implement paging
...inq (with SQL 2005 / 2008 as database server) your query will be using the Select ROW_NUMBER() Over ... statement, with is somehow direct paging in the SQL engine.
Giving you an example, I have a db table called mtcity and I wrote the following query (work as well with linq to entities):
using (Da...
sql query to return differences between two tables
...colum C, here are the records, which are present in table A but not in B:
SELECT A.*
FROM A
LEFT JOIN B ON (A.C = B.C)
WHERE B.C IS NULL
To get all the differences with a single query, a full join must be used, like this:
SELECT A.*, B.*
FROM A
FULL JOIN B ON (A.C = B.C)
WHERE A.C IS NUL...