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Maintenance of the complete path of the current directory to the variable

inna last edited by

How in postgresql in sql-cript keep the full path of the current director to the variable or the table?
I know how to put it on the screen!
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simrah

I was able to figure it out. Code

DROP TABLE tbl_pwd;
CREATE TABLE tbl_pwd(
    pwd TEXT
);
\COPY tbl_pwd FROM PROGRAM 'pwd';

SELECT * FROM tbl_pwd;

postgresql 16933

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Modelling a relationship which has multiple one-to-many parents
SQL, Database Testing • postgresql database design erd • • charlenef

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I think your table design is good and normalized. One thing that is not guaranteed yet is that if a photo references a bedroom, that bedroom should belong to the same house as the photo. You could get that with an additional UNIQUE constraint: ALTER TABLE bedroom ADD UNIQUE (houseid, bedroomid); Then the foreign key constraint could be defined as: ALTER TABLE photo ADD FOREIGN KEY (houseid, bedroomid) REFERENCES bedroom (houseid, bedroomid); An extra index is not nice from a performance angle, but you want an index on the houseid column of bedroom anyway because of the foreign key, so an additional column shouldn't hurt.
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VBNET user variable. ( Variable route)
Software Programming • net • • guilherme

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If you only need to remove the user name you can use:Environment.UserName Update:Dim ruta As String = "C:\Users\" + Environment.UserName
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Maintenance of the adapter variable in SharedPreference
Software Programming • android recyclerviewadapter • • obi

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Your adapter doesn't need to know the existence of any adapters there. He should be able to. RISK♪ Your data can come from anywhere, and RecyclerAdapter should not depend on the source of data.I'd do it like that:Let's say we get the answer from the server as a list. List<Items>♪ Make a model like:class UiItem { private final Item item; private final boolean isLiked; // любые другие поля нужные для отображения в адаптере // getters/setters } In fact, somewhere. Presenter/ViewModel We're all on this list. List<Item> We're on the list. List<UiItem>♪List<UiItem> mapToUiModel(List<Item> items){ List<UiItem> uiItems = new ArrayList(); for(Item item : items){ uiItems.add(new UiItem(item, sharedPreference.getLiked(item.id))); } return uiItems; } And we're already sending a list to the Adapter entrance where there are liquor or non-liquial elements.When you process the liquor, you keep the field. isLiked Total SharedPreference by id and in your entirety Presenter/ViewModel You run the maping and you're updating your adapter again.Not to update the entire adapter every time, but to change only the altered elements, use them. https://developer.android.com/reference/androidx/recyclerview/widget/DiffUtil ♪
A

Sum Interval of Dates within same column
SQL, Database Testing • postgresql datetime sum • • amarantha

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You can use the LEAD analytic function to obtain the next row's eventtype and eventdate alongside the current row's data: SELECT eventtype, eventdate, LEAD(eventtype) OVER (ORDER BY eventdate) AS nexttype, LEAD(eventdate) OVER (ORDER BY eventdate) AS nextdate FROM atable WHERE eventdate >= '2015-01-01 00:00:00.00' AND eventdate < '2016-01-01 23:59:59.59' Using the above query as a derived table, you can filter the output further on eventtype = 'START' AND nexttype = 'END' and get the difference total: SELECT SUM(EXTRACT(EPOCH FROM (nextdate - eventdate))) AS duration_seconds FROM ( SELECT eventtype, eventdate, LEAD(eventtype) OVER (ORDER BY eventdate) AS nexttype, LEAD(eventdate) OVER (ORDER BY eventdate) AS nextdate FROM atable WHERE eventdate >= '2015-01-01 00:00:00.00' AND eventdate < '2016-01-01 23:59:59.59' ) AS s WHERE eventtype = 'START' AND nexttype = 'END' ; As a slight variation, you can implement the subquery as a CTE: WITH cte AS ( SELECT eventtype, eventdate, LEAD(eventtype) OVER (ORDER BY eventdate) AS nexttype, LEAD(eventdate) OVER (ORDER BY eventdate) AS nextdate FROM atable WHERE eventdate >= '2015-01-01 00:00:00.00' AND eventdate < '2016-01-01 23:59:59.59' ) SELECT SUM(EXTRACT(EPOCH FROM (nextdate - eventdate))) AS duration_seconds FROM cte WHERE eventtype = 'START' AND nexttype = 'END' ; This rewrite can have implications for performance, because unlike a derived table, a CTE is materialised in PostgreSQL. Testing should reveal if there is a difference and, if so, which option is better for you.
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It is not possible to connect paths with os.path.join()
Software Programming • python python 3.x • • obi

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Your problem with the stalker is that the way to join is starting to build from the roots of the first path, that is, if you remove the lead silk (inside) \icons to iconsThat's work.import os root_path=r'c:\dummy\root\path' path_with_slash=r'\target' path_without_slash='target' print(os.path.join(root_path,path_with_slash)) # c:\target print(os.path.join(root_path,path_without_slash)) # c:\dummy\root\path\target
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Impact of CLUSTER on performance
SQL, Database Testing • postgresql performance storage index tuning postgresql performanc lan postgresql 9.2 • • Saumya

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Yes, there can be downsides. If another query looks at a different data segment not determined by the date, it might take a performance hit if rows are spread out over more data pages now. Just the same way as your first query profits. That completely depends on information not in your question. other queries using a PK of table (let say id_foo) That could be anything. It depends on what you have and what you query exactly. Querying a single row is not affected either way, but multiple rows might be. Be aware that CLUSTER rewrites the table in pristine condition like VACUUM FULL does (removes dead tuples, compacts the physical size of the table, rewrites indexes) So you might see an immediate positive effect on read performance independent of the sort order. (Much like you would get with VACUUM FULL.) After CLUSTER, you may want to run a plain VACUUM on the table to update the visibility map, too - which may allow index-only scans. All benefits of CLUSTER shrink with the write frequency. Also, if you have many updates to the table, CLUSTER can actually hurt write performance by removing "wiggle room" for HOT updates on the same data page. You might be able to counter that effect with a FILLFACTOR setting below 100. Again, depends on locality of updated rows, etc. Related: Index optimization with dates Either way, I would probably not index and cluster on my_timestamp::date, but on my_timestamp directly. Nothing lost, something gained. The cast is very cheap, but it's still cheaper not to cast at all. And the index can support more queries. CREATE INDEX foo_my_timestamp_idx ON foo (my_timestamp); Even though a date occupies only 4 bytes on disk and a timestamp occupies 8 bytes, the difference is typically lost to alignment padding for your case, and both indexes have exactly the same size. The order of multiple rows on the same day resulting from your expression index is arbitrary. There can still be two identical timestamps, but with 6 fractional digits that's normally very unlikely. Aside from that you get a deterministic order of rows, which can have various advantages. I also dropped the DESC key word since Postgres can read indexes backwards virtually as fast a forwards. (Sort order matters for multicolumn indexes, though!) More: Optimizing queries on a range of timestamps (two columns) Instead of: SELECT * FROM foo WHERE my_timestamp::date = '2016-07-25'; You would now use: SELECT * FROM foo WHERE my_timestamp >= '2016-07-25' -- this is a timestamp literal now WHERE my_timestamp < '2016-07-26'; Same performance. If you don't need the time component of the column at all, convert the column to date ... How to roll back CLUSTER? CLUSTER on a single table can be rolled back with ROLLBACK like any other regular command as long as the transaction has not been committed. However, I quote the manual: CLUSTER without any parameter reclusters all the previously-clustered tables in the current database that the calling user owns, or all such tables if called by a superuser. This form of CLUSTER cannot be executed inside a transaction block. You can always run CLUSTER with a different index to change the physical order of rows once more.
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Select number of returned rows
Software Programming • postgresql • • Nykeriab

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Yes, it is possible through the function count. The syntax is as follows:select count(*) from tabela where condição; O count can also be used in conjunction with other functions to perform a more flexible line count (e.g. count + group by).
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Is it possible to pass the value of a Javascript variable to a C# variable?
Software Programming • javascript c sharp asp.net mvc 5 • • terrea

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To pass JavaScript values to asp.net, it is necessary to make a new request (e.g. using AJAX). It is not possible to check the resolution before making the request because JS in this case is client-side, while asp.net is server-side, which means that the JS code will only run in the browser after the order that transferred the page has ended. The server does not have access to the independent JS code executed in the browser, unless you inform it directly by making a new request.But this approach is bad, because the decision to display or not a component in the navbar will depend on a second request after loading the page. The ideal thing is to do this with client-side technologies not to have to go to the server and then go back, thus saving features, accelerating page loading and not depending on JS enabled in the browser.It is possible to do this with JS, but the CSS3 introduced https://developer.mozilla.org/pt-BR/docs/Web/Guide/CSS/CSS_Media_queries , starting the movement of responsive layouts that automatically adjust according to the resolution (and the server is agnostic in relation to that). For example, to hide a navbar when the resolution is less than or equal to 600px, do so:@media (max-width: 600px) { .navbar { display: none; } }
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A, How to calculate the average of a variable x for each group of each of the other variables
Software Programming • dplyr summary • • charlenef

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Reformat for long format and then group and calculate averages all at once.library(dplyr) library(tidyr) mtcars %>% select(mpg, vs, am, gear, carb) %>% pivot_longer(-mpg) %>% group_by(name, value) %>% summarise(mean_mpg = mean(mpg))
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SQL. Integration of SELECT results into one line, replacement of results for humans required
Software Programming • postgresql select • • tahishae

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SELECT arg1, string_agg( case when arg2=1 then 'сайт' when arg2=2 then 'электронная почта' when arg2=3 then 'телефон' end,',') from tab1 where arg1=111 group by arg1 The aggregate function string_agg showed up https://www.postgresql.org/docs/9.0/functions-aggregate.html ♪ If you needre for an earlier version, please indicate the question.
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whitelist for allowed user queries in postgres
SQL, Database Testing • postgresql security • • jonetta

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Looking for a way to limited a user to a specific set of queries (i.e. a whitelist). Wrap all of your queries in a plpgsql function that takes a SQL command and executes dynamic SQL. SELECT * FROM mystupidwrapper('SELECT * FROM foo'); It will have to return a specific type, SETOF jsonb sounds great. You can write mystupidwrapper in perl, or plv8 and it'll even be trusted. If you want to write it in plperl, you can even use SQL::Statement::Structure to do basic SQL Statement processing. That said, SQL is a query language it provides READ permissions on both table and columns but the goal is still a declarative language that provides the ability to query abstractly. Perhaps you want something more like pg-promise which natively supports a QueryFile
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indicate the type of variable from another variable
Software Programming • c sharp • • esther

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I think it's a good jazz for the generos.T GetWhatever<T>() where T: class { var items = new List<T>(); GridTerminalSystem.GetBlocksOfType<T>(items); return Items.FirstOrDefault(); } and cause, respectively TextPanel tp = GetWhatever<IMyTextPanel>(); or IMyGyro gyro = GetWhatever<IMyGyro>();♪Maybe you'll need other restrictions. Tif they're imposed GetBlocksOfType♪
give variable to instance and make use of a variable of another class
Software Programming • java • • irl

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with respect to the second doubt:Yeah, you need a static variable started at 0 or 1. You can create a getter without major problems and create a setter as well but, any of the instances can modify the value of the static variable(is necessary??).public class Saltamontes { private String nombre; private static int cantidad = 0; public Saltamontes(String nombre) { // aumeto la cantidad cada vez que crea una instancia cantidad++; this.nombre = nombre; System.out.print(" "); // opcional ja } public String getNombre() { return nombre; } public void setNombre(String nombre) { this.nombre = nombre; } public static int getCantidad() { return cantidad; } public static void setCantidad(int cantidad) { Saltamontes.cantidad = cantidad; } @Override public String toString() { return nombre; } !Main testArrayList<Saltamontes> s = new ArrayList<>(); for(int i = 0; i < 10 ; i++) { s.add(new Saltamontes("juan "+(i+1))); } System.out.println(); System.out.println("Existen "+Saltamontes.getCantidad()+" "); for(Saltamontes ss : s) { System.out.println("hola soy "+ss); } ♪can create getter and setter instance by removing static or creating others with different namesWith respect to the first part of the question it is not clear to me that you want to do but, create names of variables (or new variables) in execution time, it is not recommended (* I do not know if it is possible in java, someone that corrects me if I am wrong*), uses a data structure that allows to store a variable number of instances as a arrayList or another more convenient for your application.
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SDB selection for project
Software Programming • mysql postgresql database mariadb • • baileigh

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There's a big C.O.D.IBM DB/2OracleMicrosoft SQL ServerAll three have little sons/boys like MySQL, Oracle Express, SQL Server Express, etc.There's still fashionable now NoSQL + clouds. API, etc.A few million records, it's typhoid. Large servers are needed if multiple servers are required in different media, etc.MySQL will fit your task.What to choose is like color and taste. ♪ ♪I would personally recommend Postgres.
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PostgreSQL: permission denied for relation
SQL, Database Testing • postgresql permissions authorization role • • nishika

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I just wrote about this in my answer to Granting rights on postgresql database to another user on ServerFault. Basically, the best solution when you have a single user and you want to grant other users the same rights is to turn that user into a group, create a new user with the same name as the original one that's a member of the group, and grant that group to other users too. So in your case, rails gets renamed to say myapp_users, then you create a new login role (user) named rails and GRANT myapp_users TO rails. Now you an GRANT myapp_users TO meltemi. Both the new rails account and the meltemi user now have the rights of the old railsaccount. For more fine-grained control I ususally advise that you avoid giving the day-to-day login users or their groups ownership of the tables. Give them access via a NOINHERIT group they must explicitly SET GROUP to, or better, use a completely different user for privileged operations like DDL and GRANTs. Unfortunately this doesn't work with Rails, because Rails likes to apply migrations whenever it feels like it and AFAIK doesn't give you the ability to specify a different, more-privileged user to run the migrations as.

Maintenance of the complete path of the current directory to the variable

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VBNET user variable. ( Variable route)
Software Programming • net • • guilherme

Maintenance of the adapter variable in SharedPreference
Software Programming • android recyclerviewadapter • • obi

Sum Interval of Dates within same column
SQL, Database Testing • postgresql datetime sum • • amarantha

It is not possible to connect paths with os.path.join()
Software Programming • python python 3.x • • obi

Impact of CLUSTER on performance
SQL, Database Testing • postgresql performance storage index tuning postgresql performanc lan postgresql 9.2 • • Saumya

Select number of returned rows
Software Programming • postgresql • • Nykeriab

Is it possible to pass the value of a Javascript variable to a C# variable?
Software Programming • javascript c sharp asp.net mvc 5 • • terrea

A, How to calculate the average of a variable x for each group of each of the other variables
Software Programming • dplyr summary • • charlenef

SQL. Integration of SELECT results into one line, replacement of results for humans required
Software Programming • postgresql select • • tahishae

whitelist for allowed user queries in postgres
SQL, Database Testing • postgresql security • • jonetta

indicate the type of variable from another variable
Software Programming • c sharp • • esther

give variable to instance and make use of a variable of another class
Software Programming • java • • irl

SDB selection for project
Software Programming • mysql postgresql database mariadb • • baileigh

PostgreSQL: permission denied for relation
SQL, Database Testing • postgresql permissions authorization role • • nishika