如何自学SQL？ - 知乎
SQL直来直去，只要定义必要的输入输出，没有对过程的控制。 了解SQL的大致情况后，我们再来看看如何学？ SQL是所有数据库查询的语言，sql由于本身结构化的特点，非常容易入手。
sql - NOT IN vs NOT EXISTS - Stack Overflow
Which of these queries is the faster? NOT EXISTS: SELECT ProductID, ProductName FROM Northwind..Products p WHERE NOT EXISTS ( SELECT 1 FROM Northwind..[Order Details] …
sql是什么，通俗的说，太专业听不懂？ - 知乎
SQL是一种用于处理数据的语言，就像我们说的汉语、英语一样，有特定的语法结构，让我们灵活地处理数据。 SQL并不难学，首先得理解 S Q L 三个字母分别代表什么。 Structured Query …
SQL WITH clause example - Stack Overflow
Sep 23, 2012 · 353 The SQL WITH clause was introduced by Oracle in the Oracle 9i release 2 database. The SQL WITH clause allows you to give a sub-query block a name (a process also …
How to select unique records by SQL - Stack Overflow
How to select unique records by SQL Asked 15 years, 8 months ago Modified 1 year, 6 months ago Viewed 738k times
sql server - Database stuck in "Restoring" state - Stack Overflow
Ran into a similar issue while restoring the database using SQL server management studio and it got stuck into restoring mode. After several hours of issue tracking, the following query worked …
How do I perform an IF...THEN in an SQL SELECT?
Sep 15, 2008 · The CASE statement is the closest to IF in SQL and is supported on all versions of SQL Server. SELECT CAST( CASE WHEN Obsolete = 'N' or InStock = 'Y' THEN 1 ELSE 0 …
How to set variable from a SQL query? - Stack Overflow
I'm trying to set a variable from a SQL query: declare @ModelID uniqueidentifer Select @ModelID = select modelid from models where areaid = 'South Coast' Obviously I'm not doing this right …
Convert Rows to columns using 'Pivot' in SQL Server
Apr 10, 2013 · Pivot is one of the SQL operator which is used to turn the unique data from one column into multiple column in the output. This is also mean by transforming the rows into …
sql - Exclude a column using SELECT * [except columnA] FROM …
We all know that to select all columns from a table, we can use SELECT * FROM tableA Is there a way to exclude column(s) from a table without specifying all the columns? SELECT * [except …