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Get the last inserted row ID (with SQL statement) [duplicate]

...alue using: INSERT INTO dbo.YourTable(columns....) VALUES(..........) SELECT SCOPE_IDENTITY() This works as long as you haven't inserted another row - it just returns the last IDENTITY value handed out in this scope here. There are at least two more options - @@IDENTITY and IDENT_CURRENT - r...
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Postgres: INSERT if does not exist already

...onditional INSERT in PostgreSQL: INSERT INTO example_table (id, name) SELECT 1, 'John' WHERE NOT EXISTS ( SELECT id FROM example_table WHERE id = 1 ); CAVEAT This approach is not 100% reliable for concurrent write operations, though. There is a very tiny race condition between...
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C++STL容器使用经验总结 - C/C++ - 清泛网 - 专注C/C++及内核技术

...的区间: binary_search lower_bound upper_bound equal_range set_union set_intersection set_difference set_symmetric_difference merge inplace_merge includes 下面的算法并不一定需要排序的区间: unique unique_copy 第35条:通过mismatch或lexicographical_compa...
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Comparing date ranges

... range_start, here's some simple SQL to retrieve all the matching rows: SELECT * FROM periods WHERE NOT (range_start > @check_period_end OR range_end < @check_period_start) Note the NOT in there. Since the two simple rules finds all the non-matching rows, a simple NOT will reve...
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Formatting Numbers by padding with leading zeros in SQL Server

... Change the number 6 to whatever your total length needs to be: SELECT REPLICATE('0',6-LEN(EmployeeId)) + EmployeeId If the column is an INT, you can use RTRIM to implicitly convert it to a VARCHAR SELECT REPLICATE('0',6-LEN(RTRIM(EmployeeId))) + RTRIM(EmployeeId) And the code to re...
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Why is the gets function so dangerous that it should not be used?

...deal would have been to have a "string pointer" identify a byte that would select among a few different string/buffer/buffer-info formats, with one value of prefix byte indicating a struct that contained the prefix byte [plus padding], plus the buffer size, used size, and address of the actual text....
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Why would someone use WHERE 1=1 AND in a SQL clause?

...mple code to Greg's answer: dim sqlstmt as new StringBuilder sqlstmt.add("SELECT * FROM Products") sqlstmt.add(" WHERE 1=1") ''// From now on you don't have to worry if you must ''// append AND or WHERE because you know the WHERE is there If ProductCategoryID <> 0 then sqlstmt.AppendForm...
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MySQL INNER JOIN select only one row from second table

...have multiple associated payments in the payments table. I would like to select all users who have payments, but only select their latest payment. I'm trying this SQL but i've never tried nested SQL statements before so I want to know what i'm doing wrong. Appreciate the help ...
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Best way to check for “empty or null value”

... ' Demo Empty string equals any string of spaces when cast to char(n): SELECT ''::char(5) = ''::char(5) AS eq1 , ''::char(5) = ' '::char(5) AS eq2 , ''::char(5) = ' '::char(5) AS eq3; Result: eq1 | eq2 | eq3 ----+-----+---- t | t | t Test for "null or empty string" w...
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SELECT INTO a table variable in T-SQL

Got a complex SELECT query, from which I would like to insert all rows into a table variable, but T-SQL doesn't allow it. 8...