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How does a PreparedStatement avoid or prevent SQL injection?
...);
If "user" came from user input and the user input was
Robert'); DROP TABLE students; --
Then in the first instance, you'd be hosed. In the second, you'd be safe and Little Bobby Tables would be registered for your school.
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MySQL Error 1093 - Can't specify target table for update in FROM clause
I have a table story_category in my database with corrupt entries. The next query returns the corrupt entries:
16 Answers...
Count number of occurences for each unique value
...
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 ...
SQL Server Regular expressions in T-SQL
... of people to SQL Server. The "people" are from the [Application].[People] table in the [WideWorldImporters] sample database. They get passed to the R engine as a dataframe named InputDataSet. R uses the grepl function with the "not" operator (exclamation point!) to find which people have email addr...
Split function equivalent in T-SQL?
...to split '1,2,3,4,5,6,7,8,9,10,11,12,13,14,15...' (comma delimited) into a table or table variable.
15 Answers
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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 disable scrolling in UITableView table when the content fits on the screen
I have a few (grouped style) tables in my iphone app (only on part of the screen and added with Interface Builder though, not subclassed from UITableViewController ) that 80% of the time are small and will fit on the screen. When the table fits on the screen, I'd like to disable scrolling, to ma...
How to vertically center content with variable height within a div?
...ra markup and seems to work extremely well. I couldn’t use the display: table method because table elements don’t obey the max-height property.
.block {
height: 300px;
text-align: center;
background: #c0c0c0;
border: #a0a0a0 solid 1px;
margin: 20px;
}
.block::before {
...
SQL update trigger only when column is modified
...oRepair <> I.QtyToRepair
END
END
2- Use Join between Inserted table and deleted table
ALTER TRIGGER [dbo].[tr_SCHEDULE_Modified]
ON [dbo].[SCHEDULE]
AFTER UPDATE
AS BEGIN
SET NOCOUNT ON;
UPDATE SCHEDULE
SET modified = GETDATE()
, ModifiedUser = SUSER_NAME...
SQL to find the number of distinct values in a column
...aggregate function:
SELECT COUNT(DISTINCT column_name) AS some_alias FROM table_name
This will count only the distinct values for that column.
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