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Select n random rows from SQL Server table
I've got a SQL Server table with about 50,000 rows in it. I want to select about 5,000 of those rows at random. I've thought of a complicated way, creating a temp table with a "random number" column, copying my table into that, looping through the temp table and updating each row with RAND() , and ...
Hidden Features of SQL Server
...xing table ?''',
@Command2 = 'dbcc dbreindex(''?'')',
@Command3 = 'select count (*) [?] from ?'
Also, sp_MSforeachdb
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edited Feb 17 '10 at 2:34
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Caveats of select/poll vs. epoll reactors in Twisted
...o based apps ) leads me to believe that ePoll is a natural replacement for Select and Poll based networking, especially with Twisted. Which makes me paranoid, its pretty rare for a better technique or methodology not to come with a price.
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ElasticSearch, Sphinx, Lucene, Solr, Xapian. Which fits for which usage? [closed]
... SET NAMES utf8
# query before fetching rows to index
sql_query = SELECT *, id AS pid, CRC32(safetag) as safetag_crc32 FROM hb_posts
sql_attr_uint = pid
# pid (as 'sql_attr_uint') is necessary for sphinx
# this field must be unique
# that is why I like sphinx
# you ...
How to output MySQL query results in CSV format?
...ech-recipes.com/rx/1475/save-mysql-query-results-into-a-text-or-csv-file/
SELECT order_id,product_name,qty
FROM orders
WHERE foo = 'bar'
INTO OUTFILE '/var/lib/mysql-files/orders.csv'
FIELDS TERMINATED BY ','
ENCLOSED BY '"'
LINES TERMINATED BY '\n';
Using this command columns names will not be e...
Show MySQL host via SQL Command
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To get current host name :-
select @@hostname;
show variables where Variable_name like '%host%';
To get hosts for all incoming requests :-
select host from information_schema.processlist;
Based on your last comment,
I don't think you can resolve IP...
How to show SQL queries run in the Rails console?
...ecord::Relation’s to_sql method:
User.where(:id => 3).to_sql
#=> "SELECT \"users\".* FROM \"users\" WHERE \"users\".\"id\" = 3"
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Regular expression to limit number of characters to 10
...a regular expression that will only allow lowercase letters and up to 10 characters. What I have so far looks like this:
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List all tables in postgresql information_schema
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You should be able to just run select * from information_schema.tables to get a listing of every table being managed by Postgres for a particular database.
You can also add a where table_schema = 'information_schema' to see just the tables in the informat...
ActiveRecord OR query
...here(t[:author].eq("Someone").or(t[:title].matches("%something%"))).to_sql
SELECT "posts".* FROM "posts" WHERE (("posts"."author" = 'Someone' OR "posts"."title" LIKE '%something%'))
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