Convert and organize the built-in functions in Oracle in SQL

In the program, Oracle databases and SQL databases are often supported. Some Oracle built-in functions are mostly used, but the syntax in SQL is somewhat different. I have done some sorting and hope to help you .... 1. built-in functions in oracle: round functions in oracle (rounding) (SQL can also be used) returned by trunc in oracle

In the program, Oracle databases and SQL databases are often supported. Some Oracle built-in functions are mostly used, but the syntax in SQL is somewhat different. I have done some sorting and hope to help you .... 1. built-in functions in oracle: round functions in oracle (rounding) (SQL can also be used) returned by trunc in oracle

In the program, Oracle databases and SQL databases are often supported. Some Oracle built-in functions are mostly used in Hong Kong space, but the syntax in SQL is somewhat different. I have done some sorting and I hope to help you with the website space ....

1. built-in functions in oracle:
Round Function in oracle (rounding) (SQL can also be used)
Trunc in oracle Returns [00:00:00] of the current day.
In oracle, the floor and floor (n) values are the largest integers less than or equal to the value n (SQL can also be used)
The length function in oracle is len in SQL Server.
In oracle, The datalength function in sqlserver is datalength.
Change the lob_to_char function in oracle to convert (char, opertime, 120)
Change the to_char function in oracle to convert (char, opertime, 120)
Change the substr function in oracle to substring.
Example: select convert (char, getdate (), 120) -- yyyy-mm-dd hh: mm: ss (24 h)
Convert (char, SubmitTime, 120) = convert (char, getdate (), 120)
In oracle, change floor (sysdate-trunc (opertime) to datediff (dd, convert (varchar (100), InputDate, 111), convert (varchar (100), getdate (), 111 ))
Change dbms_lob.getlength in oracle to datalength (Change Clob type to NText type in sqlserver database)
Change ROWNUM in oracle to row_number () OVER (order by xx) and the SQL statement must contain top
For example, in SQL:
SELECT * FROM (
Select a. *, row_number () OVER (order by a. MATTERID) as rn from (
SELECT * FROM ATTACHMENT_T)
) T where rn <= 20 and rn> = 0

2. Oacle system table dual
Certificate to sqlserver directly remove dual

3. Errors and solutions:
SqlDateTime overflow. It must be between 1/1/1753 12:00:00 AM and 12/31/9999 11:59:59 PM
Modify the constructor and server space in the model and assign the DateTime type to the attribute.
ElementContent_Model, OperLog_Model