I want to run select Sql Server Query at one time. I am using Drill in embedded mode.
select * from <storagePluginName1>.<schemaName>.<tableName>;
select * from <storagePluginName2>.<schemaName>.<tableName>;
Example:-
select * from SqlServer.dbo.`Category`;
select * from sqldemo.dbo.`Attributes`;
Whether Apache Drill Supports Multiple Query at one
time or not.??? If Yes then How.??
So, you are running in embedded mode and want to run multiple queries in parallel from sqlline. Here is how to do it:
after you start Drill, do to the webUI and check the value displayed for "User Port", let's say it's: 172.30.1.119:31010
you can create other sqlline instances connected to the same Drillbit by running
sqlline -u jdbc:drill:drillbit=172.30.1.119:31010
Now you will be able to submit parallel queries from those sqlline instances. You can check in the webUI that the queries are running at the same time indeed.
Unfortunately the answer is NO, at least from the version I used(1.15). Drill parser would regards the ';' separator as an illegal character.
0: jdbc:drill:drillbit=localhost:3001> select 1; select 1;
Error: PARSE ERROR: Encountered ";" at line 1, column 9.
Was expecting one of:
...
Related
I'm trying to query a secure bucket via couchbase CBQon windows.
I've got couchbase/bin in my PATH and from the command line I am able to run this:
cbq -engine=http://localhost:8091 -c=hug_contenthub:password
seems to connect OK:
Connected to : http://localhost:8091/. Type Ctrl-D or \QUIT to exit.
Path to history file for the shell : C:\Users\kevin\.cbq_history
cbq>_
From here on I can't do anything except quit. I tried several commands:
cbq> select 1=1
> SELECT DISTINCT type FROM `beer-sample`
> create primary index on `beer-sample`
They are all ignored. No feedback at all. The only thing that changes is cqb> becomes "....>" the cqb bit is stripped off.
What am I missing here?
I'm relatively new to Couchbase Server, and I'm used to the old MS SQL ways, and so I think I had a similar problem.
My solution: I added a 'semicolon' at the end of each query.
I also tend to prefer to use the new Query Workbench tool instead of cbq when I'm just writing and tweaking N1QL queries. (But maybe that's just me).
We are connecting Hadoop cloudera CDH distribution through ODBC driver. Queries are generated from SSRS. Few queries are working fine with parameters augmented through ? placeholder. Few other queries with parameters augmented through ? are not executing.
Error [HY000][Cloudera][ImpalaODBC] (100) error while executing a query in Impala[HY000] : AnalysisException : syntax error in line 1 where Date >= ? and Date <= ?
^Encountered : Unexpected characterExpected : Case... Exception : syntax error.
If i remove where Date >= ? and Date <= ? or supply the hard coded value then query is working perfect.
Few other queries with same filter are working perfect.
What should be recommended investigation points?
Where could i get the exact impala transformed query to investigate whether query is generated correct or not ?
You have a couple of options:
/var/log/impalad/audit stores audit logs (at least in CDH). Those logs contain sql_statement field that stores executed sql queries
Impala has a web server running on a 25000 port. You could connect
with your browser and see queries executed (/queries tab).
If you are using Cloudera Manager, you could see all executed impala
queries in "impala/queries"
I have a CRON job which executes a SELECT statement to grab records. When the SELECT runs on my dev machine, it produces the following statement:
SELECT `users`.* FROM `users` WHERE `users`.`id` = 87 LIMIT 1
This is successful.
When the SELECT runs on my production (hosted) machine it produces the statement with double quotes:
SELECT "users".* FROM "users" WHERE "users”.”id” = 87 LIMIT 1
This is not successful and I get a MySQL 1064 error,
#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '.* FROM "users" WHERE "users
The code is the same on both machines, but my dev MySQL is version 5.5.33, whereas production is 5.1.67 (I don't have control over this to set/update it)
Is there a way to force single quotes or another preferred method to handle this situation?
Thanks for your time and assistance.
--EDIT--
Here are the main code snippets that are invoked via my CRON job:
/lib/tasks/reports.rake
namespace :report do
desc "Send Daily Report"
task :daily => :environment do
User.where(:report_daily => 1).find_each do |user|
ReportsMailer.send_report(user, 'daily').deliver
end
end
/app/mailers/reports_mailer.rb
def send_report(user, date_increment)
#user = user
#date_increment = date_increment
get_times(user)
mail :to => user.email, :subject=> "Report: #{#dates}"
end
--EDIT2--
So it looks like I need to use slanted single quotes (`) in order for this to work successfully. How do I force my app or MySQL to use these instead of double (") quotes?
I don't know why it does this, but I do know that if you're referencing column names in MYSQL, you need to use ``, whereas values / data should be wrapped in "", like this:
SELECT `users`.* FROM `users` WHERE `users`.`id` = "87" LIMIT 1
I learnt this the hard way back in the day when I was learning how to do simple MYSQL queries
Here's some documentation from MYSQL's site for you:
The identifier quote character is the backtick (“`”):
mysql> SELECT * FROM `select` WHERE `select`.id > 100;
Identifier quote characters can be included within an identifier if
you quote the identifier. If the character to be included within the
identifier is the same as that used to quote the identifier itself,
then you need to double the character. The following statement creates
a table named a`b that contains a column named c"d:
mysql> CREATE TABLE `a``b` (`c"d` INT);
Is there any reason you couldn't put some of your sql statement directly into your code like:
User.where("`report_daily`=1").find_each do |user|
After further inspection, and working with my hosting company, its turns out that my query is timing out on their server. Thanks to all that responded.
Since you are not using any literals, the format of the generated SQL statements should be determined by the underlying adapter. Perhaps you have a different mysql adapter installed or configured on each machine. Check the installed version. For example:
bundle show mysql
and also check the adapter configuration for your project in database.yml. For example:
adapter: mysql
A comparison of the results of these checks between each machine should tell you if you are using different adapters on the two machines.
The following is generated query from Hibernate (except I replaced the list of fields with *):
select *
from
resource resource0_,
resourceOrganization resourceor1_
where
resource0_.active=1
and resource0_.published=1
and (
resource0_.resourcePublic=1
or resourceor1_.resource_id=resource0_.id
and resourceor1_.organization_id=2
and (
resourceor1_.resource_id=resource0_.id
and resourceor1_.forever=1
or resourceor1_.resource_id=resource0_.id
and (
current_date between resourceor1_.startDate and resourceor1_.endDate
)
)
)
Currently I have 200+ records in both the Windows and Linux databases and currently for each record, the following happens to be true:
active = 1
published = 1
resourcePublic = 1
When I run this directly in a SQL client, this SQL query gets me all the matching records on Windows but none on Linux. I've MySQL 5.1 on both Windows and Linux.
If I apply the Boolean logic, (true and true and (true or whatever)), I expect the outcome to be true. It indeed is true on Windows but false on Linux!!!
If I modify the query as the following, it works on both Windows and Linux:
select *
from
resource resource0_
where
resource0_.active=1
and resource0_.published=1
and (
resource0_.resourcePublic=1
)
So, just the presence of conditions related to resourceOrganization is making the query bring 0 results on Linux and I expected that since it is the second part of an 'or' condition whose first part is true, the outcome should be true.
Any idea why this difference in behavior between the 2 OSs and why what should obviously work on Linux doesn't!
Thanks in advance!
Check the case sensitivity and collation sets (Collation issues)
Check the table case sensitivity. In particular note that on windows the table names are case-insensitive and on Linux they are case-sensitive.
Have you tried a simple test case on both system?
Check that current_date() returns the same format in both plataforms
I notice that the second test query only consults the resource table not the resourceOrganisation table.
I suspect that the table resourceOrganisation is populated differently on the two machines, and the corresponding rows may not exist in your Linux MySQL.
What does this query return?
select *
from
resource resource0_,
resourceOrganization resourceor1_
where
resource0_.active=1
and resource0_.published=1
and (
resource0_.resourcePublic=1
or resourceor1_.resource_id=resource0_.id
and resourceor1_.organization_id=2
)
Also don't forget to check the collation and case sensitivity, if one server uses a different collation to the other then you will have this same issue.
We have a lot of queries
select * from tbl_message
that get stuck on the state "Writing to net". The table has 98k rows.
The thing is... we aren't even executing any query like that from our application, so I guess the question is:
What might be generating the query?
...and why does it get stuck on the state "writing to net"
I feel stupid asking this question, but I'm 99,99% sure that our application is not executing a query like that to our database... we are however executing a couple of querys to that table using WHERE statement:
SELECT Count(*) as StrCount FROM tbl_message WHERE m_to=1960412 AND m_restid=948
SELECT Count(m_id) AS NrUnreadMail FROM tbl_message WHERE m_to=2019422 AND m_restid=440 AND m_read=1
SELECT * FROM tbl_message WHERE m_to=2036390 AND m_restid=994 ORDER BY m_id DESC
I have searched our application several times for select * from tbl_message but haven't found anything... But still our query-log on our mysql server is full of Select * from tbl_message queries
Since applications don't magically generate queries as they like, I think that it's rather likely that there's a misstake somewhere in your application that's causing this. Here's a few suggestions that you can use to track it down. I'm guessing that your using PHP, since your using MySQL, so I'll use that for my examples.
Try adding comments in front of all your queries in the application, like this:
$sqlSelect = "/* file.php, class::method() */";
$sqlSelect .= "SELECT * FROM foo ";
$sqlSelect .= "WHERE criteria";
The comment will show up in your query log. If you're using some kind database api wrapper, you could potentially add these messages automatically:
function query($sql)
{
$backtrace = debug_backtrace();
// The function that executed the query
$prev = $backtrace[1];
$newSql = sprintf("/* %s */ ", $prev["function"]);
$newSql .= $sql;
mysql_query($newSql) or handle_error();
}
In case you're not using a wrapper, but rather executing the queries directly, you could use the runkit extension and the function runkit_function_rename to rename mysql_query (or whatever you're using) and intercept the queries.
There are (at least) two data retrieval modes for mysql. With the c api you either call mysql_store_result() or mysql_use_result().
mysql_store_result() returns when all result data is transferred from the MySQL server to your process' memory, i.e. no data has to be transferred for further calls to mysql_fetch_row().
However, by using mysql_use_result() each record has to be fetched individually if and when mysql_fetch_row() is called. If your application does some computing that takes longer than the time period specified in net_write_timeout between two calls to mysql_fetch_row() the MySQL server considers your connection to be timed out.
Temporarily enable the query log by putting
log=
into your my.cnf file, restart mysql and watch the query log for those mystery queries (you don't have to give the log a name, it'll assume one from the host value).