I feel like I am missing something, but I could not find it in the documentation on GH.
What are the escape characters for Blazer when searching in a string that contains a ' or ".
Example:
SELECT * FROM "search_filters"
where "params" like '%with_vehicles_id"=>[%'
LIMIT 100
Update:
The underlying database is Postgres 11. This is a blazer tool question, as the query above works just fine in a tool like dBeaver, or console. For some reason, I believe this is related to how Blazer is parsing the query before it is sent.
I'm not very familiar with Blazer but it looks like it's a BI tool that lets your run SQL queries against your database and there's a playground here.
For PostgreSQL you don't need to do anything special for a double-quote inside of single quotes. The query as you wrote it would execute in a postgres terminal and the same approach works in the blazer playground.
SELECT * FROM "search_filters"
where "params" like '%text"text%'
LIMIT 100
To query on a string that includes a single quote, PosgreSQL has you use two sequential single quotes, like this:
SELECT * FROM "search_filters"
where "params" like '%text''text%'
LIMIT 100
Here's a link with more information:
https://www.prisma.io/dataguide/postgresql/short-guides/quoting-rules
-- UPDATE --
Based on your error message ("syntax error at or near "LIMIT" LINE 3: LIMIT 100 LIMIT 1000") it looks like there are two "LIMIT" clauses being added to the SQL query. Do you have gems/plugins that are modifying the query and is there a way to disable them to see if that's causing the problem?
Related
I'm trying to get an exact field from multiple measurements with the same naming pattern.
Let's say the measurements are like:
some.stats.123
some.stats.456
some.stats.789
I'm trying to get test value, this is possible with:
select test from "some.stats.123";
and I would like to call it like:
select test from "some.stats.*";
The above query is accepted by influx but returns nothing. What am I missing here?
Turns out regex can be used here instead of wildcard:
select test from /some.stats.*/
works like charm :)
I was trying to write a simple FluxQL Query in Grafana Dashboard that uses a variable
m1(of type constant)(which contains the name of the measurement)
I created the variable m1 in grafana dashboard variables
m1 = my-measurement
and tried to run the following queries but non of them worked and they either say expression request error or No Data)
i.e
SELECT count("fails") FROM "/^${m1:raw}$/"
SELECT count("fails") FROM "/^${m1}$/"
SELECT count("fails") FROM $m1" (expression request error)
SELECT count("fails") FROM "$m1"
SELECT count("fails") FROM "${m1}"
The only query worked was without dashboard variables
SELECT count("fails") FROM "my-measurement"
How can I use the variables to work for that query.
On the similar ground I tried to make a custom variable(myVar) for which we take integer input values from user and on that basis where clause should work, but same error occurs either no data or expression request error
What I tried was
SELECT count(*) from "my-measurement-2" WHERE ("value" > $myVar)
How should I solve these issues?Please help
You may have a problem with
1.) syntax
SELECT count("fails")
FROM "${m1:raw}"
2.) data
You may correct query syntax, but query can be very inefficient. Query execution may need a lot of time - so it's better to have timefilter, which will use selected dashboard time range (make sure you have some data in that time range)
SELECT count("fails")
FROM "${m1:raw}"
WHERE $timeFilter
3.) Grafana panel configuration
Make sure you are using suitable panel - for query above Stat panel is a good option (that query returns only single value, not timeseries, so time series panel types may have a problem with that).
Generally, use query inspector to see how are variables interpolated - there can be "magic", which is not obvious - e.g. quotes which are added around numeric variables, so then it is string filtering and not numeric filtering on the InfluxDB level.
I have a plain SQL query written by a trusted administrator that is to be run in a Rails (4.2) app. I am sanitizing it with ActiveRecord::Base.send(:sanitize_sql, ...) to allow user inputs to act as conditions, using the ? character for bind variables. The code has to allow arbitrary SQL, so I'm not interested in the arguments about why this is not the Rails way, etc.
The problem is that I can not include ? in a result field in the SQL without the underlying replace_bind_variables method replacing an intended literal ? in the result.
A simple query for example would be:
select 'http://www.google.com?q=' || res from some_table where a = ?;
To sanitize:
ActiveRecord::Base.send(:sanitize_sql, [sql, 'not me'], :some_table)
The sanitization fails because the ? in the URL gets replaced with the data intended for the condition, leading to the exception:
ActiveRecord::PreparedStatementInvalid: wrong number of bind variables (1 for 2)
The question is, does sanitize_sql or some variant allow literal ? characters to be included in a query so that they are not replaced? Is there some way of escaping them?
In the end I read through the ActiveRecord source and couldn't identify a way to handle this situation without a lot of code changes. There doesn't appear to be a way to escape the ? characters.
To resolve it for this one query I ended up using the SQL chr() function to generate a character that would pass the santization step untouched:
select 'http://www.google.com' || chr(63) || 'q=' || res from some_table where a = ?;
ASCII character 63 is ?.
Although not a perfect solution, I could at least get this one SQL query into the system without having to make massive code changes.
I have something like this
var query = repo.GetQuery(); // IQueryable
query.Where(item => item.FieldName.Contains("xxx%yyy"));
It results in following statement on SQL server
exec sp_executesql N'SELECT
// clipped
WHERE ([Extent1].[FieldName] LIKE #p__linq__0 ESCAPE N''~'')',
N'#p__linq__0 nvarchar(4000),#p__linq__0=N'%xxx~%yyy%'
#p__linq__0=N'%xxx~%yyy% causes the SQL server to look for xxx%yyy with % as literal (as it is escaped) while I would like it to match string like xxx123yyy, xxxABCyyy, xxxANYTHINGyyy, xxxyyy etc. Addition of prefix % and suffix % is fine but I could do it manually if needed.
In the above example I have simplified and written only one where condition but I have a dynamic logic that build the predicate with many of such keywords and I would like to allow the wildcards to be embedded inside the keywords. Is there a way to tell EF not to escape the % in the search keyword?
It is not possible. Contains("xxx") means that in SQL you want LIKE '%xxx%'. Linq-to-entities and none of its String mapped methods offer full wildcard searching = any wildcard character is always escaped. If you want to use wildcard searching you must use Entity SQL.
I'm executing an SQLite select statement with several LIKE clauses in an iPhone application. The statements resemble the following:
SELECT * FROM mytable
WHERE name LIKE 'Smith %'
OR name LIKE '% Smith %'
OR name LIKE 'Smith_%'
OR name LIKE '% Smith_%';
The execution currently takes about 0.5 seconds on my laptop and about 2 seconds on the device. I can't index the "name" column of "mytable" because of space constraints.
Each of the LIKE clauses is quite similar - if one fails, it's likely they each will. So I'd like to group these together some how to optimize my search.
Can this be done, say via REGEXP? If so, how and is REGEXP enabled by default?
Edit. I'm trying statements along the lines of:
SELECT * FROM mytable WHERE name REGEXP '[ _]?Smith[ _,]';
SQLite actually has a full text search engine built in. You may want to consider using it.
http://www.sqlite.org/fts3.html#section_1