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Restrict varchar() column to specific values?
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128
Have you already looked at adding a check constraint on that column which would restrict value...
How to add a filter class in Spring Boot?
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162
If you want to setup a third-party filter you can use FilterRegistrationBean.
For example the ...
SQL how to increase or decrease one for a int column in one command
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To answer the first:
UPDATE Orders SET Quantity = Quantity + 1 WHERE ...
To answer the second:
There are several ways to do this. Since you did not specify a database, I will assume MySQL.
INSERT INTO table SET x=1, y=2 ON DUPLICATE KEY UPDATE x=x+1, y=y+2
REPLACE INTO table SET ...
delete_all vs destroy_all?
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edited May 23 '17 at 12:26
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answered Jul 14 '11 at 18:36
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How to silence output in a Bash script?
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189
If it outputs to stderr as well you'll want to silence that. You can do that by redirecting fi...
What is the difference between tinyint, smallint, mediumint, bigint and int in MySQL?
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581
They take up different amounts of space and they have different ranges of acceptable values.
He...
Gradle alternate to mvn install
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174
sdk/build.gradle:
apply plugin: "maven"
group = "foo"
version = "1.0"
example/build.gradle...
Using {} in a case statement. Why?
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195
The {} denotes a new block of scope.
Consider the following very contrived example:
switch (...
Delete rows from a pandas DataFrame based on a conditional expression involving len(string) giving K
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184
When you do len(df['column name']) you are just getting one number, namely the number of rows ...