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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 do I size a UITextView to its content?
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Tested on iOS 7 to resize an UITextView into an UITableViewCell. Works really great. This is the only answer that finally worked for me. Thanks!
– Alex
Nov 30 '13 at 18:40
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How do I execute a stored procedure once for each row returned by query?
... way. I pass it user_id and it does it's thing. I want to run a query on a table and then for each user_id I find run the stored procedure once on that user_id
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SQL Server dynamic PIVOT query?
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Dynamic SQL PIVOT:
create table temp
(
date datetime,
category varchar(3),
amount money
)
insert into temp values ('1/1/2012', 'ABC', 1000.00)
insert into temp values ('2/1/2012', 'DEF', 500.00)
insert into temp values ('2/1/2012', 'GHI',...
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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How to delete duplicate rows in SQL Server?
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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...
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:
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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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REST URI convention - Singular or plural name of resource while creating it
...from our database schema. And database standards tend to advocate singular table names, so we're going with that, but still under the same logic as this answer.
– André C. Andersen
Nov 24 '17 at 12:01
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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...