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Number of rows affected by an UPDATE in PL/SQL
...s with the number of line affected by the last DML operation:
say we have table CLIENT
create table client (
val_cli integer
,status varchar2(10)
)
/
We would test it this way:
begin
dbms_output.put_line('Value when entering the block:'||sql%rowcount);
insert into client
se...
ORA-00979 not a group by expression
...ave a database like this:
FOO BAR
0 A
0 B
and you run SELECT * FROM table GROUP BY foo. This means the database must return a single row as result with the first column 0 to fulfill the GROUP BY but there are now two values of bar to chose from. Which result would you expect - A or B? Or shou...
How do I check if a column is empty or null in MySQL?
I have a column in a table which might contain null or empty values. How do I check if a column is empty or null in the rows present in a table?
...
When/Why to use Cascading in SQL Server?
...eal key rather than a surrogate key (identity/autoincrement column) across tables.
The canonical example for Cascade Update is when you have a mutable foreign key, like a username that can be changed.
You should not use Cascade Update with keys that are Identity/autoincrement columns.
Cascade Updat...
How do I horizontally center a span element inside a div
...
another option would be to give the span display:table; and center it via margin:0 auto;
span {
display:table;
margin:0 auto;
}
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What does the “@” symbol do in Powershell?
...l V2, @ is also the Splat operator.
PS> # First use it to create a hashtable of parameters:
PS> $params = @{path = "c:\temp"; Recurse= $true}
PS> # Then use it to SPLAT the parameters - which is to say to expand a hash table
PS> # into a set of command line parameters.
PS> dir @para...
How to check if a database exists in SQL Server?
...ing the INFORMATION_SCHEMA views rather than directly accessing the system tables.
– mwigdahl
Mar 24 '09 at 20:09
4
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How to define a custom ORDER BY order in mySQL
...age,'ENU','JPN','DAN'), ID
Note however, that
It makes your SQL less portable, as other DBMSs might not have such function
When your list of languages (or other values to sort by) gets much longer, it's better to have a separate table with sortorder column for them, and join it to your queries fo...
SQL select only rows with max value on a column [duplicate]
I have this table for documents (simplified version here):
27 Answers
27
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How does virtual inheritance solve the “diamond” (multiple inheritance) ambiguity?
... be only 1 instance of the base A class not 2.
Your type D would have 2 vtable pointers (you can see them in the first diagram), one for B and one for C who virtually inherit A. D's object size is increased because it stores 2 pointers now; however there is only one A now.
So B::A and C::A are...