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Does the join order matter in SQL?
... neither predicate can be satisfied by a row in which all columns from one table are NULL, than to say that it's associative as long as the predicates don't involve IS NULL or 'a function that is related to nulls'. One can easily imagine a predicate that satisfies the former description but not the ...
How to delete duplicate rows in SQL Server?
...
RN = ROW_NUMBER()OVER(PARTITION BY col1 ORDER BY col1)
FROM dbo.Table1
)
DELETE FROM CTE WHERE RN > 1
DEMO (result is different; I assume that it's due to a typo on your part)
COL1 COL2 COL3 COL4 COL5 COL6 COL7
john 1 1 1 1 1 1
sa...
How to COUNT rows within EntityFramework without loading contents?
I'm trying to determine how to count the matching rows on a table using the EntityFramework.
7 Answers
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When and why are database joins expensive?
...nality when (if) they set up indexes.
It is important to understand that table scans (examination of every row in a table in the course of producing a join) are rare in practice. A query optimiser will choose a table scan only when one or more of the following holds.
There are fewer than 200 row...
MySQL INSERT INTO table VALUES.. vs INSERT INTO table SET
What is main difference between INSERT INTO table VALUES .. and INSERT INTO table SET ?
3 Answers
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How exactly does __attribute__((constructor)) work?
...fferently organized than .init/.fini. .ctors/.dtors sections are both just tables with pointers to functions, and the "caller" is a system-provided loop that calls each function indirectly. I.e. the loop-caller can be architecture specific, but as it's part of the system (if it exists at all i.e.) i...
1052: Column 'id' in field list is ambiguous
I have 2 tables. tbl_names and tbl_section which has both the id field in them. How do I go about selecting the id field, because I always get this error:
...
Maximum length of a table name in MySQL
What is the maximum length of a table name in MySQL?
4 Answers
4
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Insert multiple rows WITHOUT repeating the “INSERT INTO …” part of the statement?
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INSERT INTO dbo.MyTable (ID, Name)
SELECT 123, 'Timmy'
UNION ALL
SELECT 124, 'Jonny'
UNION ALL
SELECT 125, 'Sally'
For SQL Server 2008, can do it in one VALUES clause exactly as per the statement in your question (you just need to add a comm...
How to insert a row in an HTML table body in JavaScript
I have an HTML table with a header and a footer:
9 Answers
9
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