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MySQL: determine which database is selected?
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DUAL is an Oracle table, that was taken over into MySQL. It's a dummy table for operations that do not require an actual table. en.wikipedia.org/wiki/DUAL_table
– Jan Thomä
Nov 11 '11 at 16:03
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PHP + MySQL transactions examples
...b_passwd,$db_name); // error-check this
// note: this is meant for InnoDB tables. won't work with MyISAM tables.
try {
$conn->autocommit(FALSE); // i.e., start transaction
// assume that the TABLE groups has an auto_increment id field
$query = "INSERT INTO groups (name) ";
$qu...
2 column div layout: right column with fixed width, left fluid
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Simplest and most flexible solution so far it to use table display:
HTML, left div comes first, right div comes second ... we read and write left to right, so it won't make any sense to place the divs right to left
<div class="container">
<div class="left">
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Border around tr element doesn't show?
... not render borders on tr , but it renders the border if the selector is table tr td .
1 Answer
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SQL to determine minimum sequential days of access?
The following User History table contains one record for every day a given user has accessed a website (in a 24 hour UTC period). It has many thousands of records, but only one record per day per user. If the user has not accessed the website for that day, no record will be generated.
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is there a post render callback for Angular JS directive?
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Humm, try something like: <table id="bob"><tbody dashboard-table="#bob"></tbody></table> Then in your link, do $(attrs.dashboardTable).dataTable() to make sure it's being selected right. Or I guess you already tried that.. I'm real...
How do you perform a left outer join using linq extension methods
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For a (left outer) join of a table Bar with a table Foo on Foo.Foo_Id = Bar.Foo_Id in lambda notation:
var qry = Foo.GroupJoin(
Bar,
foo => foo.Foo_Id,
bar => bar.Foo_Id,
(x,y) => new { Foo = x, Bars = y...
What is the string length of a GUID?
...haracter string.
Here is an example.
USE AdventureWorks2008R2;
GO
CREATE TABLE MyCcustomerTable
(
user_login varbinary(85) DEFAULT SUSER_SID()
,data_value varbinary(1)
);
GO
INSERT MyCustomerTable (data_value)
VALUES (0x4F);
GO
Applies to: SQL Server
The following example create...
When and why are database joins expensive?
...nality when (if) they set up indexes.
It is important to understand that table scans (examination of every row in a table in the course of producing a join) are rare in practice. A query optimiser will choose a table scan only when one or more of the following holds.
There are fewer than 200 row...
Oracle find a constraint
...stem generated constraint name. For instance, if we specify NOT NULL in a table declaration. Or indeed a primary or unique key. For example:
SQL> create table t23 (id number not null primary key)
2 /
Table created.
SQL> select constraint_name, constraint_type
2 from user_constraint...