I'm a complete and total newb at SQL. I know how to correlate data between tables, but that's pretty much it (and then, only if I have GUI...). I am attempting to write some automated tests for a site we are working on.
The project I'm working on contains 2 schema for users that register to the site. From time to time, we use the other, for "private" users. When they register, the users that go to the "private" site also go in the second schema.
Basically, during the writing of my tests, whenever I need a registration token from the default schema, I use this SQL command in my tests (which I write using Java code):
select tokenValue from Tokens where TypeOfToken = 'REGISTRATION' and user_id = '48'
This works without problems, since the default schema is already specified elsewhere.
Is there a way for me to specify from which schema I need to select the token from?
Thank you.
select tokenValue from [Insert Schema here without brackets].Tokens where TypeOfToken = 'REGISTRATION' and user_id = '48'
Related
I have a query like Select '16453842' AS ACCOUNT, I want to change this Account number to a dynamic one. Can anyone tell me what are some possible ways to do it?
The scenario is like, I would also like to accommodate other values as well for the ACCOUNT. So that multiple values can be used for ACCOUNT.
the Nodejs code uses that sql in below code by carrierData.sql
writeDebug({'shipment': shipment, 'carrier': carrier, 'message': 'reading sql file: ' + carrierData.sql});
fs.readFile(carrierData.sql, 'utf8', function (err, sql) {
The carrierData is coming from a json file from where the sql contains the path and name of the SQL which it is going to use. And finally the SQL file which have the query runs a query like below
SELECT 'T' AS RECORD
, '16453842' AS ACCOUNT
and here lies my problem as we have some additional ACCOUNT numbers as well which we would like to accommodate.
And the service starts by node server.js which will call the workers.js file which contains the code that I pasted above.
So please let me know what can be the possible ways to do this
Here are things to research:
Using bind variables. These are used for security and for performance when a statement is executed multiple times.
Using multiple values in IN clauses.
Using executeMany() if you are loading data into the database.
I am writing this post because I have encountered something truly weird with an SQL statement I am trying to make.
Context:
I am developing an app which uses JPA in the backend to persist / retrieve objects to/from a postgres database.
Problem:
During some tests I have noticed that when a particular user adds entries in the database and later I try to fetch them by his facebook id, the result is an empty list, even though the entries are there in the database. Doing a select statement on the database returns no rows. This does not happen with other users.
I have noticed that the mentioned user's facebook id is slightly longer then others. I do not know if and how this affects this situation.
Interesting part:
When during debugging I created an entry not programmatically, but manually with a SQL INSERT statement directly on the database (marked red on the 1st screenshot), I could fetch the data by facebook id both in my app and with a select statement.
Do you have any ideas what is going on here?
Please check the screenshots:
result of select * from table:
result of select * from table where user_facebook_id = 10215905779020408 :
Please help,
Thanks
In SQL Server (2016) we have the SESSION_CONTEXT() and sp_set_session_context to retrieve/store custom variables in a key-value store. These values are available only in the session and their lifetime ends when the session is terminated. (Or in earlier versions the good old CONTEXT_INFO to store some data in a varbinary).
I am looking for a similar solution in EXASol (6.0).
An obvious one would be to create a table and store this info there, however this requires scheduled cleanup script and more error prone than a built-in solution. This is the fallback plan, however I'd like to be sure that there is no other options.
Another option could be to create individual users in the database and configure them, but just because of the amount of users to be added, this was ruled out.
The use-case is the following: An application has several users, each user have some values to be used in each queries. The application have access only to some views.
This works wonderfully in SQL Server, but we want to test EXASol as an alternative with the same functionality.
I cannot find anything related in the EXASol Manual but it is possible, that I just missed something.
Here is a simplified sample code in SQL Server 2016
sp_set_session_context #key='filter', #value='asd', #read_only=1;
CREATE VIEW FilteredMyTable AS
SELECT Col1, Col2, Col3 FROM MyTable
WHERE MyFilterCol = CONVERT(VARCHAR(32), SESSION_CONTEXT('filter'))
I've tried an obviously no-go solution, just to test if it works (it does not).
ALTER SESSION SET X_MY_CUSTOM_FILTER = "asd"
You cannot really set a session parameter in EXASOL, the only way to achieve something similar is to store the values that you need in a table with a structure like:
SESSION_ID KEY VALUE READ_ONLY
8347387 filter asd 1
With LUA you could create a script that will make easier for you to manage these "session" variables.
I think you can achieve what you need by using the scripting capabilities within Exasol - see section 3.5 in the user manual..
You could also handle the parameterisation 'externally' via a shell script
I'm trying to get work my play20 application with postgresql so I can use and later deploy to Heroku. I followed this answer.
Basically, I made connection to database (so connection from local application to Heroku postgresql database worked), but I was not able to initialise database with generated 1.sql evolution. But generated sql was not working because of postgresql is using schema (it should work without schema anyway, but apparently I'm doing something wrong or database is doing something wrong).
create table user (
id bigint not null,
email varchar(255),
gender varchar(1),
constraint pk_user primary key (id));
resulted in
ERROR: syntax error at or near "user"
Position: 14 [ERROR:0, SQLSTATE:42601]
I fixed that with adding schema to table name
create table public.user(
...
);
Ok, everything worked until I tried to read or write to database. I got again sql syntax exception and can't work with database. Seems like sql queries are somehow wrong.
Any suggestions where could be problem?
That's very common mistake while developing application with other database than in production, but fortunately there is also common solution. You can still use User model, however you have to make sure that creates database table with changed name:
#Entity
#Table(name = "users")
public class User extends Model {
...
}
In most cases in your controllers and models name-switch will be transparent for you. Only place where you have to remember the switch are RawSql queries.
BTW, that's good idea to install locally the same database for developing cause there's a lot of differences between most popular databases, like other reserved keywords, other allowed types, even other auto incrementing methods for id, so finding and fixing proper values is just easier on localhost.
Well, due to my little knowledge about postgresql, I was struggling with this all day. Here's simple solution. Don't use table called "user" on postgreqsl. This table is already used.
But why my evolution sql query worked for initialisation of database? Well if I explicitly specify in which schema I want to create table "user", that basically works.
But if schema is not specified, is used current schema. From documentation:
If a schema name is given (for example, CREATE TABLE myschema.mytable ...) then the table is created in the specified schema. Otherwise it is created in the current schema
So that explains it. But for my project, using "user" model was perfectly reasonable and for H2 file based databased it was working, so I assumed that problem was somewhere else...
Im having trouble identifying my databases as correct and valid version of my model. I have a GUID-id for my model I could use, but where do I put it? I dont want an entire table with only one row for this GUID. Is there any metadata-repository for databases (SQL Server 2008) or is there any other methods of identifying databases except their names? I could name the database to my model-GUID but it doesnt seem right...
The scenario is like this: I have a Entity Framework-model and I identify it by a GUID. I let the user pick a database-connectionstring and now I want to verify that its a valid database (which has been created from my app). I want to do this every time the app starts just to be sure. What Im doing now is checking that a certain table with a certain name exists but thats not good enough. I want to be 99% sure.
Edit: I would prefer to set this value from the DDL-script which is already setting up the database and I want to be able to get it from a SqlCommand in ado.net.
Use an Extended database property
In script:
USE preet;
GO
EXEC sys.sp_addextendedproperty
#name = N'myVersion',
#value = N'999-abc-123-nop';
GO
and
In the UI