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SQL Server: What is the difference between CROSS JOIN and FULL OUTER JOIN?
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select COUNT_BIG(*) FROM Traffic t CROSS JOIN Recipient r and SELECT COUNT_BIG(*) FROM Traffic t FULL JOIN Recipient r ON (1=1) they are the same.
– urlreader
Sep 20 '13 at 21:02
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Jdbctemplate query for string: EmptyResultDataAccessException: Incorrect result size: expected 1, ac
...ce is you call ResultSet.next().
public String test() {
String sql = "select ID_NMB_SRZ from codb_owner.TR_LTM_SLS_RTN "
+ " where id_str_rt = '999' and ID_NMB_SRZ = '60230009999999'";
return jdbc.query(sql, new ResultSetExtractor<String>() {
@Override
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How to COUNT rows within EntityFramework without loading contents?
... where o.ID == '1'
from t in o.MyTable
select t).Count();
Method syntax:
var count = context.MyContainer
.Where(o => o.ID == '1')
.SelectMany(o => o.MyTable)
.Count()
Both generate the same SQL query.
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mysql_fetch_array()/mysql_fetch_assoc()/mysql_fetch_row()/mysql_num_rows etc… expects parameter 1 to
I am trying to select data from a MySQL table, but I get one of the following error messages:
31 Answers
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UPDATE multiple tables in MySQL using LEFT JOIN
...= t1.id
SET t1.col1 = newvalue
WHERE t2.id IS NULL
Note that for a SELECT it would be more efficient to use NOT IN / NOT EXISTS syntax:
SELECT t1.*
FROM t1
WHERE t1.id NOT IN
(
SELECT id
FROM t2
)
See the article in my blog for performance details...
Generating a random & unique 8 character string using MySQL
...umn:
INSERT INTO vehicles VALUES (blah); -- leaving out the number plate
SELECT @lid:=LAST_INSERT_ID();
UPDATE vehicles SET numberplate=concat(
substring('ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789', rand(@seed:=round(rand(@lid)*4294967296))*36+1, 1),
substring('ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789'...
How enumerate all classes with custom class attribute?
... faster (especially without empirical proof); you've basically written the Select extension method, and the compiler will generate a state machine just as it would if you called Select because of your use of yield return. Finally, any performance gains that might be obtained in the majority of case...
LINQPad [extension] methods [closed]
...QueryLanguage.Expression, @"from c in Customers
where c.Name.Length > 3
select c.Name", "Click to run!").Dump();
You can also write your own extension methods in LINQPad. Go to 'My Queries' and click the query called 'My Extensions'. Any types/methods that define here are accessible to all quer...
LEFT OUTER joins in Rails 3
...OUTER JOIN users ON users.id = posts.user_id").
joins(:blog).select
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Code Wrap IntelliJ?
...o right click the gutter (the vertical bar where line number is shown) and select "Use Soft wraps" - thanks to Bajal for comment.
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