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What does SQL clause “GROUP BY 1” mean?
Someone sent me a SQL query where the GROUP BY clause consisted of the statement: GROUP BY 1 .
6 Answers
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DBMS_OUTPUT.PUT_LINE not printing
...e executes. Most tools, on the other hand, have the ability to do so. In SQL*Plus, you'd need to use the command set serveroutput on [size N|unlimited]. So you'd do something like
SQL> set serveroutput on size 30000;
SQL> exec print_actor_quotes( <<some value>> );
In SQL Deve...
Delimiters in MySQL
...tements are each terminated by ;. That way, when the code is run in the mysql client, the client can tell where the entire procedure ends and execute it as a unit rather than executing the individual statements inside.
Note that the DELIMITER keyword is a function of the command line mysql client (...
Returning IEnumerable vs. IQueryable
...ifference is that IQueryable<T> is the interface that allows LINQ-to-SQL (LINQ.-to-anything really) to work. So if you further refine your query on an IQueryable<T>, that query will be executed in the database, if possible.
For the IEnumerable<T> case, it will be LINQ-to-object, ...
Altering column size in SQL Server
...olumn with a straight “ALTER TABLE” command, you will have to wait for SQLServer to go through all the rows and write the new data type
ALTER TABLE tab_name ALTER COLUMN col_name new_larger_data_type;
To overcome this inconvenience, there is a magic column enlargement pill that your table...
SQL Server: Is it possible to insert into two tables at the same time?
...e atomic, and can be sent to the server from a client application with one sql string in a single function call as if it were one statement. You could also apply a trigger to one table to get the effect of a single insert. However, it's ultimately still two statements and you probably don't want to...
SQL/mysql - Select distinct/UNIQUE but return all columns?
I am trying to accomplish the following sql statement but I want it to return all columns is this possible? Something like:
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SQL: deleting tables with prefix
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You cannot do it with just a single MySQL command, however you can use MySQL to construct the statement for you:
In the MySQL shell or through PHPMyAdmin, use the following query
SELECT CONCAT( 'DROP TABLE ', GROUP_CONCAT(table_name) , ';' )
AS statement F...
What makes a SQL statement sargable?
...t on the subject matter. So the question is, what does or doesn't make an SQL query sargable? Any documentation would be greatly appreciated.
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LINQ to SQL: Multiple joins ON multiple Columns. Is this possible?
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Joining on multiple columns in Linq to SQL is a little different.
var query =
from t1 in myTABLE1List // List<TABLE_1>
join t2 in myTABLE1List
on new { t1.ColumnA, t1.ColumnB } equals new { t2.ColumnA, t2.ColumnB }
...
You have to take a...