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In Postgresql, force unique on combination of two columns
I would like to set up a table in PostgreSQL such that two columns together must be unique. There can be multiple values of either value, so long as there are not two that share both.
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PDO Prepared Inserts multiple rows in single query
... fields to create the ? placeholders to bind your parameters.
insert into table (fielda, fieldb, ... ) values (?,?...), (?,?...)....
That is basically how we want the insert statement to look like.
Now, the code:
function placeholders($text, $count=0, $separator=","){
$result = array();
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Access denied for user 'root'@'localhost' while attempting to grant privileges. How do I grant privi
...er_priv: Y
Show_db_priv: Y
Super_priv: Y
Create_tmp_table_priv: Y
Lock_tables_priv: Y
Execute_priv: Y
Repl_slave_priv: Y
Repl_client_priv: Y
Create_view_priv: Y
Show_view_priv: Y
Create_routine_priv: Y
Alter_routine_priv: Y
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COUNT DISTINCT with CONDITIONS
...tinct items in a column subject to a certain condition, for example if the table is like this:
5 Answers
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sqlalchemy: how to join several tables by one query?
...teger primary keys for everything, but whatever):
class User(Base):
__tablename__ = 'users'
email = Column(String, primary_key=True)
name = Column(String)
class Document(Base):
__tablename__ = "documents"
name = Column(String, primary_key=True)
author_email = Column(String,...
SQL Case Sensitive String Compare
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Select * from a_table where attribute = 'k' COLLATE Latin1_General_CS_AS
Did the trick.
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Effect of NOLOCK hint in SELECT statements
...2) Yes, a select with NOLOCK will allow other queries against the effected table to complete faster than a normal select.
Why would this be?
NOLOCK typically (depending on your DB engine) means give me your data, and I don't care what state it is in, and don't bother holding it still while you re...
Does the join order matter in SQL?
... neither predicate can be satisfied by a row in which all columns from one table are NULL, than to say that it's associative as long as the predicates don't involve IS NULL or 'a function that is related to nulls'. One can easily imagine a predicate that satisfies the former description but not the ...
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'];
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How to make an empty div take space
...p;nbsp; to the empty items.
I don't understand why you're not using a <table> here, though? They will do this kind of stuff automatically.
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