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Changing the maximum length of a varchar column?
...characters to 500 without losing the contents. I've dropped and re-created tables before but I've never been exposed to the alter statement which is what I believe I need to use to do this. I found the documentation here: ALTER TABLE (Transfact-SQL) however I can't make heads or tails of it.
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MySQL InnoDB not releasing disk space after deleting data rows from table
I have one MySQL table using the InnoDB storage engine; it contains about 2M data rows. When I deleted data rows from the table, it did not release allocated disk space. Nor did the size of the ibdata1 file reduce after running the optimize table command.
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Sql Server 'Saving changes is not permitted' error ► Prevent saving changes that require table re-cr
When I create a table in SQL Server and save it, if I try to edit the table design, like change a column type from int to real, I get this error:
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CSS display: table min-height not working
...e know I can make min-height work with the latest browsers? I am using CSS tables and it seems to ignore min-height.
4 Answ...
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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Count number of occurences for each unique value
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Perhaps table is what you are after?
dummyData = rep(c(1,2, 2, 2), 25)
table(dummyData)
# dummyData
# 1 2
# 25 75
## or another presentation of the same data
as.data.frame(table(dummyData))
# dummyData Freq
# 1 1 ...
How to copy a row and insert in same table with a autoincrement field in MySQL?
... row with an autoincrement column ID=1 and insert the data into same table as a new row with column ID=2 .
13 Answer...
Altering a column to be nullable
I want to alter a table column to be nullable. I have used:
10 Answers
10
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How can I join multiple SQL tables using the IDs?
I have 4 different tables that I want to join. The tables are structured with columns as follows:
4 Answers
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Define variable to use with IN operator (T-SQL)
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DECLARE @MyList TABLE (Value INT)
INSERT INTO @MyList VALUES (1)
INSERT INTO @MyList VALUES (2)
INSERT INTO @MyList VALUES (3)
INSERT INTO @MyList VALUES (4)
SELECT *
FROM MyTable
WHERE MyColumn IN (SELECT Value FROM @MyList)
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