What is the difference between SQL, PL-SQL and T-SQL?
网页2015年1月26日 · SQL is a data oriented language for selecting and manipulating sets of data. PL/SQL is a procedural language to create applications. – user610835. Feb 10, 2011 at 4:55. SQL is structured query language PL/SQL is a procedural language extended to sql it is developed by oracle T-SQL is developed by microsoft. – user782314.
Should I use != or <> for not equal in T-SQL? - Stack Overflow
网页2009年4月6日 · Yes; Microsoft themselves recommend using <> over != specifically for ANSI compliance, e.g. in Microsoft Press training kit for 70-461 exam, "Querying Microsoft SQL Server", they say "As an example of when to choose the standard form, T-SQL supports two “not equal to” operators: <> and !=. The former is standard and the latter is …
What are the differences between T-SQL, SQL Server and SQL
网页2013年9月19日 · 7. 1.SQL is a programming language while T-SQL is an extension to SQL. 2.T-SQL is proprietary while SQL is an open format. 3.T-SQL contains procedural programming, local variable, and such while SQL does not. 4.T-SQL is Turing complete while SQL is not.
t sql - How to check if a column is empty or null using SQL query ...
网页Here is my preferred way to check for "if null or empty": SELECT *. FROM UserProfile. WHERE PropertydefinitionID in (40, 53) AND NULLIF(PropertyValue, '') is null. Since it modifies the search argument (SARG) it might have performance issues because it might not use an existing index on the PropertyValue column.
sql server - T-sql - determine if value is integer - Stack Overflow
网页This is the only really reliable way. Should you need support for SQL-Server 2008, then fall back to Sam DeHaan's answer: SELECT CASE WHEN ISNUMERIC(@foo + '.e0') = 1 THEN 1 ELSE 0 END AS isInteger. SQL-Server < 2012 (aka 2008R2) will reach end of (extended) support by 2019-07-09.
sql server - PRINT statement in T-SQL - Stack Overflow
网页2008年11月6日 · The Print statement in TSQL is a misunderstood creature, probably because of its name. It actually sends a message to the error/message-handling mechanism that then transfers it to the calling application. PRINT is pretty dumb. You can only send 8000 characters (4000 unicode chars).
T-SQL: Selecting rows to delete via joins - Stack Overflow
网页2016年2月22日 · Employees) and one with a child set (eg. Dependents) and you're wanting to get rid of all the rows of data in the Dependents table that cannot key up with any rows in the Master table. delete from Dependents where EmpID in (. select d.EmpID from Employees e. right join Dependents d on e.EmpID = d.EmpID.
sql server - Most efficient T-SQL way to pad a varchar on the left …
网页2008年9月23日 · As compared to say: REPLICATE(@padchar, @len - LEN(@str)) + @str
sql - Not equal <> != operator on NULL - Stack Overflow
网页2014年10月9日 · In SQL, anything you evaluate / compute with NULL results into UNKNOWN. This is why SELECT * FROM MyTable WHERE MyColumn != NULL or SELECT * FROM MyTable WHERE MyColumn <> NULL gives you 0 results. To provide a check for NULL values, isNull function is provided. Moreover, you can use the IS …
How do I perform an IF...THEN in an SQL SELECT?
网页2008年9月15日 · See working demo: if then without case in SQL Server. For start, you need to work out the value of true and false for selected conditions. Here comes two NULLIF: for true: ISNULL(NULLIF(p.[Instock], 'Y'), 1) for false: ISNULL(NULLIF(p.[Instock], 'N'), 0) combined together gives 1 or 0. Next use bitwise operators.