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MySQL, Check if a column exists in a table with SQL
...query and I think it needs a small alteration to get it working properly.
SELECT *
FROM information_schema.COLUMNS
WHERE
TABLE_SCHEMA = 'db_name'
AND TABLE_NAME = 'table_name'
AND COLUMN_NAME = 'column_name'
That worked for me.
Thanks!
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How can I remove duplicate rows?
...
Assuming no nulls, you GROUP BY the unique columns, and SELECT the MIN (or MAX) RowId as the row to keep. Then, just delete everything that didn't have a row id:
DELETE FROM MyTable
LEFT OUTER JOIN (
SELECT MIN(RowId) as RowId, Col1, Col2, Col3
FROM MyTable
GROUP BY Co...
PostgreSQL query to return results as a comma separated list
Let say you have a SELECT id from table query (the real case is a complex query) that does return you several results.
5 ...
How can I selectively merge or pick changes from another branch in Git?
... git rebase -i to get the original commit to edit, then git reset HEAD^ to selectively revert changes, then git commit to commit that bit as a new commit in the history.
There is another nice method here in Red Hat Magazine, where they use git add --patch or possibly git add --interactive which all...
How to find all the tables in MySQL with specific column names in them?
... all tables with columns columnA or ColumnB in the database YourDatabase:
SELECT DISTINCT TABLE_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE COLUMN_NAME IN ('columnA','ColumnB')
AND TABLE_SCHEMA='YourDatabase';
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Where IN clause in LINQ [duplicate]
...yTable
where myInClause.Contains(x.SomeColumn)
select x;
// OR
var results = MyTable.Where(x => myInClause.Contains(x.SomeColumn));
In the case of your query, you could do something like this...
var results = from states in _objectdatasource.StateList()
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How to drop all user tables?
...
BEGIN
FOR cur_rec IN (SELECT object_name, object_type
FROM user_objects
WHERE object_type IN
('TABLE',
'VIEW',
'MATERIAL...
Convert Month Number to Month Name Function in SQL
...
A little hacky but should work:
SELECT DATENAME(month, DATEADD(month, @mydate-1, CAST('2008-01-01' AS datetime)))
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Spring Boot JPA - configuring auto reconnect
...1.3
spring.datasource.testOnBorrow=true
spring.datasource.validationQuery=SELECT 1
As djxak noted in the comment, 1.4+ defines specific namespaces for the four connections pools Spring Boot supports: tomcat, hikari, dbcp, dbcp2 (dbcp is deprecated as of 1.5). You need to check which connection po...
How to map and remove nil values in Ruby
...blem:
N = 1_00_000
enum = 1.upto(1_000)
Benchmark.bmbm do |x|
x.report("select + map") { N.times { enum.select { |i| i.even? }.map{|i| i + 1} } }
x.report("map + compact") { N.times { enum.map { |i| i + 1 if i.even? }.compact } }
x.report("filter_map") { N.times { enum.filter_map { |i| i ...