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INNER JOIN ON vs WHERE clause
...ed is a cartesian product of the tables to which a filter is applied which selects only those rows with joining columns matching.
It's easier to see this with the WHERE syntax.
As for your example, in MySQL (and in SQL generally) these two queries are synonyms.
Also note that MySQL also has a STR...
Return anonymous type results?
... join b in db.Breeds on d.BreedId equals b.BreedId
select new DogWithBreed()
{
Dog = d,
BreedName = b.BreedName
};
return result;
}
It means you have an extra class, ...
How to get first character of a string in SQL?
...
SELECT SUBSTR(thatColumn, 1, 1) As NewColumn from student
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Restful way for deleting a bunch of items
...away with the javascript confirm on the same page, and instead, create the selection and redirect to it, showing a confirm message on that page. In other words:
From:
http://example.com/resources/
do a
POST with a selection of the ID's to:
http://example.com/resources/selections
which, if succes...
How to get the selected radio button’s value?
...r working. I just want to find the value of the radio button (which one is selected) and return it to a variable. For some reason it keeps returning undefined .
...
How can I get column names from a table in SQL Server?
... much more by querying the Information Schema views.
This sample query:
SELECT *
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = N'Customers'
Can be made over all these DB objects:
CHECK_CONSTRAINTS
COLUMN_DOMAIN_USAGE
COLUMN_PRIVILEGES
COLUMNS
CONSTRAINT_COLUMN_USAGE
CONSTRAINT_...
How to find all duplicate from a List? [duplicate]
...d then filter out any of the enumerables that have a Count of <=1, then select their keys to get back down to a single enumerable:
var duplicateKeys = list.GroupBy(x => x)
.Where(group => group.Count() > 1)
.Select(group => group.Key);
...
How do I see all foreign keys to a table or column?
...
For a Table:
SELECT
TABLE_NAME,COLUMN_NAME,CONSTRAINT_NAME, REFERENCED_TABLE_NAME,REFERENCED_COLUMN_NAME
FROM
INFORMATION_SCHEMA.KEY_COLUMN_USAGE
WHERE
REFERENCED_TABLE_SCHEMA = '<database>' AND
REFERENCED_TABLE_NAME = '<...
Best way to work with dates in Android SQLite [closed]
...ing (that is newest date goes first):
public static final String QUERY = "SELECT table._id, table.dateCol FROM table ORDER BY table.dateCol DESC";
//...
Cursor cursor = rawQuery(QUERY, null);
cursor.moveToFirst();
while (!cursor.isAfterLast()) {
// Process results
}
Al...
python-pandas and databases like mysql
...a_conn = cx_Oracle.connect('your_connection_string')
df_ora = pd.read_sql('select * from user_objects', con=ora_conn)
print 'loaded dataframe from Oracle. # Records: ', len(df_ora)
ora_conn.close()
And here is the equivalent example for MySQLdb:
import MySQLdb
mysql_cn= MySQLdb.connect(host='...