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SQL UPDATE SET one column to be equal to a value in a related table referenced by a different column
...ver MySQL. In my case, the source and destination columns are in the same table, but record selection is based on the other table. The "SELECT" version of the query works, but the UPDTATE statement throws a syntax error at "FROM"
– 2NinerRomeo
Mar 4 '15 at 19...
How to add new column to MYSQL table?
I am trying to add a new column to my MYSQL table using PHP. I am unsure how to alter my table so that the new column is created. In my assessment table I have:
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Updating MySQL primary key
I have a table user_interactions with 4 columns:
3 Answers
3
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Can I use a min-height for table, tr or td?
I am trying to show some details of a receive in a table.
7 Answers
7
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Entity Framework: One Database, Multiple DbContexts. Is this a bad idea? [closed]
...ngle context per app can be expensive if the application has many entities/tables. Thus depending on the schema, it might also make sense to have multiple contexts.
– DarthVader
May 13 '13 at 7:04
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Most efficient way to remove special characters from string
...ms.
The price to pay is, of course, the initialization of the huge lookup table and keeping it in memory. Well, it's not that much data, but it's much for such a trivial function...
private static bool[] _lookup;
static Program() {
_lookup = new bool[65536];
for (char c = '0'; c <= '9'; ...
What does mysql error 1025 (HY000): Error on rename of './foo' (errorno: 150) mean?
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You usually get this error if your tables use the InnoDB engine. In that case you would have to drop the foreign key, and then do the alter table and drop the column.
But the tricky part is that you can't drop the foreign key using the column name, but instea...
LINQ to SQL Left Outer Join
..."left" row in a left-outer-join will match 0-n "right" rows (in the second table), where-as yours matches only 0-1. To do a left outer join, you need SelectMany and DefaultIfEmpty, for example:
var query = from c in db.Customers
join o in db.Orders
on c.CustomerID equals o...
Restoring MySQL database from physical files
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A MySQL MyISAM table is the combination of three files:
The FRM file is the table definition.
The MYD file is where the actual data is stored.
The MYI file is where the indexes created on the table are stored.
You should be able to rest...
How can I use UUIDs in SQLAlchemy?
...uuid.UUID(bytes=value)
else:
return None
def is_mutable(self):
return False
id_column_name = "id"
def id_column():
import uuid
return Column(id_column_name,UUID(),primary_key=True,default=uuid.uuid4)
# Usage
my_table = Table('test',
metadata,
...