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SQL Joins Vs SQL Subqueries (Performance)?
... and an explicit JOIN. In my experience IN is a very slow operator, since SQL normally evaluates it as a series of WHERE clauses separated by "OR" (WHERE x=Y OR x=Z OR...).
As with ALL THINGS SQL though, your mileage may vary. The speed will depend a lot on indexes (do you have indexes on both I...
SQL Server dynamic PIVOT query?
...
Dynamic SQL PIVOT:
create table temp
(
date datetime,
category varchar(3),
amount money
)
insert into temp values ('1/1/2012', 'ABC', 1000.00)
insert into temp values ('2/1/2012', 'DEF', 500.00)
insert into temp values ...
SQL - Query to get server's IP address
Is there a query in SQL Server 2005 I can use to get the server's IP or name?
10 Answers
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How do I view the SQL generated by the Entity Framework?
How do I view the SQL generated by entity framework ?
22 Answers
22
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Search for one value in any column of any table inside a database
...a UID of the type char(64) ) inside any column of any table inside one MS SQL Server database?
7 Answers
...
Is there any difference between “!=” and “” in Oracle Sql?
...r all other DBMS - most of them support both styles):
Here is the current SQL reference: https://docs.oracle.com/database/121/SQLRF/conditions002.htm#CJAGAABC
The SQL standard only defines a single operator for "not equals" and that is <>
...
SQL left join vs multiple tables on FROM line?
Most SQL dialects accept both the following queries:
11 Answers
11
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SQL select join: is it possible to prefix all columns as 'prefix.*'?
I'm wondering if this is possible in SQL. Say you have two tables A and B, and you do a select on table A and join on table B:
...
SQL statement to select all rows from previous day
I am looking for a good SQL Statement to select all rows from the previous day from one table. The table holds one datetime column. I am using SQL Server 2005.
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SQL update from one Table to another based on a ID match
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I believe an UPDATE FROM with a JOIN will help:
MS SQL
UPDATE
Sales_Import
SET
Sales_Import.AccountNumber = RAN.AccountNumber
FROM
Sales_Import SI
INNER JOIN
RetrieveAccountNumber RAN
ON
SI.LeadID = RAN.LeadID;
MySQL and MariaDB
UPDATE
Sales_Impor...