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How to remove a lua table entry by its key?
I have a lua table that I use as a hashmap, ie with string keys :
1 Answer
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Only read selected columns
...hs (7 columns) for each year of the data below, for example by using read.table() ?
4 Answers
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sql server invalid object name - but tables are listed in SSMS tables list
.... However the SSMS intellisense does not recognize more than half of the tables which have been created.
16 Answers
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FIND_IN_SET() vs IN()
I have 2 tables in my database. One is for orders, and one is for companies.
6 Answers
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Update multiple columns in SQL
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Try this:
UPDATE table1
SET a = t2.a, b = t2.b, .......
FROM table2 t2
WHERE table1.id = t2.id
That should work in most SQL dialects, excluding Oracle.
And yes - it's a lot of typing - it's the way SQL does this.
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Import CSV to SQLite
I'm trying to import a csv file to an SQLite table.
10 Answers
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Insert, on duplicate update in PostgreSQL?
...LICT clause. with the following syntax (similar to MySQL)
INSERT INTO the_table (id, column_1, column_2)
VALUES (1, 'A', 'X'), (2, 'B', 'Y'), (3, 'C', 'Z')
ON CONFLICT (id) DO UPDATE
SET column_1 = excluded.column_1,
column_2 = excluded.column_2;
Searching postgresql's email group ar...
JOIN queries vs multiple queries
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if you are joining 3 or more tables on different keys, often databases (i.e. mysql) can only use one index per table, meaning maybe one of the joins will be fast (and use an index) whereas the others will be extremely slow. For multiple queries, you can ...
In C/C++ what's the simplest way to reverse the order of bits in a byte?
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If you are talking about a single byte, a table-lookup is probably the best bet, unless for some reason you don't have 256 bytes available.
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How to pass table value parameters to stored procedure from .net code
I have a SQL Server 2005 database. In a few procedures I have table parameters that I pass to a stored proc as an nvarchar (separated by commas) and internally divide into single values. I add it to the SQL command parameters list like this:
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