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Postgres manually alter sequence
... ALTER SEQUENCE [sequence] RESTART WITH (SELECT MAX(col) from table); does not work, whereas SELECT setval('sequence', (SELECT (MAX(col) from table), TRUE); does work. I get a syntax error. (Postgres 9.4)
– NuclearPeon
Jul 21 '18 at 1:35
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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...
SQL DROP TABLE foreign key constraint
If I want to delete all the tables in my database like this, will it take care of the foreign key constraint? If not, how do I take care of that first?
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How can prepared statements protect from SQL injection attacks?
...SELECT * FROM users where id=1
while this code
$spoiled_data = "1; DROP TABLE users;"
$query = "SELECT * FROM users where id=$spoiled_data";
will produce a malicious sequence
SELECT * FROM users where id=1; DROP TABLE users;
It works because we are adding the data directly to the prog...
SQL Server Output Clause into a scalar variable
Is there any "simple" way to do this or I need to pass by a table variable with the "OUTPUT ... INTO" syntax?
3 Answers
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How to efficiently build a tree from a flat structure?
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Store IDs of the objects in a hash table mapping to the specific object. Enumerate through all the objects and find their parent if it exists and update its parent pointer accordingly.
class MyObject
{ // The actual object
public int ParentID { get; set; ...
How to join (merge) data frames (inner, outer, left, right)
...f performance is a major issue for you, you should also look into the data.table package - that's a whole new set of join syntax, but it's radically faster than anything we're talking about here.
– Matt Parker
Feb 12 '13 at 16:22
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Is the LIKE operator case-sensitive with MSSQL Server?
...al_cp1_cs_as
(d) To create a column using a different collation
create table exampletable (
examplecolumn varchar(10) collate sql_latin1_general_cp1_ci_as null
)
(e) To modify a column collation
alter table exampletable
alter column examplecolumn varchar(10) collate sql_latin1_general_cp1...
select count(*) from table of mysql in php
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here is the code for showing no of rows in the table with PHP
$sql="select count(*) as total from student_table";
$result=mysqli_query($con,$sql);
$data=mysqli_fetch_assoc($result);
echo $data['total'];
...
Using CSS td width absolute, position
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This may not be what you want to hear, but display: table-cell does not respect width and will be collapsed based on the width of the entire table. You can get around this easily just by having a display: block element inside of the table cell itself whose width you specify, ...