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How to return result of a SELECT inside a function in PostgreSQL?
... bigint
, ratio bigint) AS
$func$
BEGIN
RETURN QUERY
SELECT t.txt
, count(*) AS cnt -- column alias only visible inside
, (count(*) * 100) / _max_tokens -- I added brackets
FROM (
SELECT t.txt
FROM token t
WHERE t.charty...
Importing a Maven project into Eclipse from Git
...t. M2Eclipse will help you along by prompting you on the Import menu.
Select the "Import..." context menu from the Package Explorer view
Select "Check out Maven projects from SCM" option under the Maven category
On the window that is presented choose the link "Find more SCM connectors in the m2...
UITableView Cell selected Color?
...f the cell other than the default [blue color] values for highlighting the selection of cell.
I use this code but nothing happens:
...
Oracle: If Table Exists
...
declare
c int;
begin
select count(*) into c from user_tables where table_name = upper('table_name');
if c = 1 then
execute immediate 'drop table table_name';
end if;
end;
That's for checking whether a table in the current schema exi...
Postgresql SELECT if string contains
...eld of the record. Concatenate using '||' with the literal percent signs:
SELECT id FROM TAG_TABLE WHERE 'aaaaaaaa' LIKE '%' || tag_name || '%';
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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!
...
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 ...
How to get the mysql table columns data type?
...
You can use the information_schema columns table:
SELECT DATA_TYPE FROM INFORMATION_SCHEMA.COLUMNS
WHERE table_name = 'tbl_name' AND COLUMN_NAME = 'col_name';
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im...
SQL Server Linked Server Example Query
...a Linked Server in SSMS Object Explorer, right-click, and Script Table as, SELECT To, and New Query Editor Window. The resulting SELECT statement will include the correct, fully-qualified path to the table. I had a mystery database qualifier in working with Sybase and this gave me the correct name.
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