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How can I return pivot table output in MySQL?
If I have a MySQL table looking something like this:
8 Answers
8
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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 ...
Hibernate: Automatically creating/updating the db tables based on entity classes
...ts it should be hibernate.hbm2ddl.auto
A value of create will create your tables at sessionFactory creation, and leave them intact.
A value of create-drop will create your tables, and then drop them when you close the sessionFactory.
Perhaps you should set the javax.persistence.Table annotation e...
How to delete all rows from all tables in a SQL Server database?
How to delete all rows from all tables in a SQL Server database?
11 Answers
11
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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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How to drop unique in MySQL?
...you can use the following SQL Script to delete the index in MySQL:
alter table fuinfo drop index email;
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How can I get column names from a table in Oracle?
...he database to get the column names , not to be confused with data in the table. For example, if I have a table named EVENT_LOG that contains eventID , eventType , eventDesc , and eventTime , then I would want to retrieve those field names from the query and nothing else.
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Adding an identity to an existing column
I need to change the primary key of a table to an identity column, and there's already a number of rows in table.
19 Answe...
SQL Server Management Studio won't let me add an index to a table
When I right click on the indexes folder in the table the "New Index" menu item is grayed out. I don't understand why. I've deleted all data in the table just in case, and refreshed and restarted SSMS, but no luck. I'm using SQL Server 2012 Business Intelligence SP1 CTP.
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MYSQL import data from csv using LOAD DATA INFILE
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You can use LOAD DATA INFILE command to import csv file into table.
Check this link MySQL - LOAD DATA INFILE.
LOAD DATA LOCAL INFILE 'abc.csv' INTO TABLE abc
FIELDS TERMINATED BY ','
ENCLOSED BY '"'
LINES TERMINATED BY '\r\n'
IGNORE 1 LINES
(col1, col2, col3, col4, col5...);
For...