Do postgres shortcuts like \d+ tablename work with RPostgreSQL?
If I try to run 'em I get a syntax error: Error: '\d' is an unrecognized escape in character string starting "\d".
I tried escape it, but did not figure it out. RPostgreSQL itself works -- I can access and query my database.
No. These are "psql metacommands" and only recognised by the psql command-line interpreter. Only SQL commands can be passed through RPostgreSQL to the Postgres database.
Related
I have a dataframe of 10M rows which needs to be uploaded back from R to Vertica Database.
The DBwrite() function from DBI is running into memory issues and I have tried increasing memory to 16g by
options(java.parameters = c("-XX:+UseConcMarkSweepGC", "-Xmx16g"))
Still the process is running into memory issue. I am planning to use bulk copy option of vertica to copy the csv file to create the table.
I have created an empty table on vertica
When I am executing the query
dbSendQuery(vertica, "COPY hpcom_usr.VM_test FROM LOCAL \'/opt/mount1/musoumit/MarketBasketAnalysis/Code/test.csv\' enclosed by \'\"\' DELIMITER \',\' direct REJECTED DATA \'./code/temp/rejected.txt\' EXCEPTIONS \'./code/temp/exceptions.txt\'")
I am running into this error.
Error in .verify.JDBC.result(r, "Unable to retrieve JDBC result set", :
Unable to retrieve JDBC result set
JDBC ERROR: [Vertica]JDBC A ResultSet was expected but not generated from query "COPY hpcom_usr.VM_test FROM LOCAL '/opt/mount1/musoumit/MarketBasketAnalysis/Code/test.csv' enclosed by '"' DELIMITER ',' direct REJECTED DATA './code/temp/rejected.txt' EXCEPTIONS './code/temp/exceptions.txt'". Query not executed.
Please help with what i'm doing wrong here.
Vertica also provides STDIN option aswell. Link
Please help me how can I execute this.
My Environment.
CENT OS 7
R 3.6.3 (No R Studio here I have to execute this from CLI)
Tidyverse 1.0.x
Vertica driver 9.x
System 128GB Memory and 28Core system.
Your problem is that you fire dbSendQuery() , which lives with a following dbFetch() and a final dbClearResult() - but only for query SQL statements - those that actually return a result set.
Vertica's COPY <table> FROM [LOCAL] 'file.ext' ... command is treated like a DML command. And for those - as this docu says ...
https://www.rdocumentation.org/packages/DBI/versions/0.5-1/topics/dbSendQuery
.. you need to use dbSendStatement() for data manipulation statements.
Have a go at it that way - good luck ...
dbSendUpdate(vertica, "COPY hpcom_usr.VM_test FROM LOCAL \'/opt/mount1/musoumit/MarketBasketAnalysis/Code/test.csv\' enclosed by \'\"\' DELIMITER \',\' direct REJECTED DATA \'./code/temp/rejected.txt\' EXCEPTIONS \'./code/temp/exceptions.txt\'")
instead of dbSendQuery did the trick for me.
I want to execute the following statement on postgresql sending it from R:
tname = 'foo'
con = some_connection_to_postgresql
q = paste("\\COPY", tname, "FROM 'foo.csv';")
dbGetQuery(con, q)
However, when I execute it, I get the following error:
Error: <SQL> '\COPY foo FROM 'foo.csv''
nanodbc/nanodbc.cpp:1587: 42601: ERROR: syntax error at or near "\";
Error while executing the query
However, the same script written from the terminal works perfectly fine.
\copy is not a postgresql statement. the psql CLI converts \copy...from filename into copy ... from stdin; and then pipes the file's contents over the postgres connection.
you'll have to do the same if you want to use copy.
I am trying to execute a SQL Query through R to get the data from Access DB
Normal SQL statement works fine, but when it comes to like statement its throwing error
Below is code :
library(RODBC);
channel = odbcDriverConnect("Driver={Microsoft Access Driver (*.mdb, *.accdb)};DBQ=C:/Users/ADMIN/Documents/R.accdb")
test = sqlQuery(channel ,paste('SELECT R.ID, R.Template, R.WEDate FROM R WHERE R.Template Like "*slow*"'))
Error:
[1] "07002 -3010 [Microsoft][ODBC Microsoft Access Driver] Too few parameters. Expected 2."
[2] "[RODBC] ERROR: Could not SQLExecDirect 'SELECT R.ID, R.Template, R.WEDate FROM R WHERE (R.Template Like \"slow\")'
Is there a way to fix this.
Consider both of #joran's suggestions with single quote enclosing string literals AND using the ANSI-92 wildcard operator %. You would use asterisk, * (ANSI-89 mode) when running an internal query, namely inside the MSAccess.exe GUI program (which defaults to DAO) or if you connect externally to Access with DAO. Meanwhile, ADO connections uses the percent symbol which most external interfaces uses including RODBC.
I was able to reproduce your issue and both these remedies worked. Also, no need to use paste() as you are not concatenating any other object to query statement.
library(RODBC);
channel = odbcDriverConnect("Driver={Microsoft Access Driver (*.mdb, *.accdb)};
DBQ=C:/Users/ADMIN/Documents/R.accdb")
test = sqlQuery(channel,
"SELECT R.ID, R.Template, R.WEDate FROM R WHERE R.Template Like '%slow%'")
i using start terminal
-macbook:sqlTest user1$ sqlite3 sqlTest.sqlite
SQLite version 3.7.13 2012-07-17 17:46:21
Enter ".help" for instructions
Enter SQL statements terminated with a ";"
sqlite> ATTACH DATABASE 'encrypted.sqlite' AS encrypted KEY 'testkey';
sqlite> SELECT sqlcipher_export('encrypted');
Error: no such function: sqlcipher_export
sqlite>
what makes no such function: sqlcipher_export?
As answered on the mailing list:
The first step is to build the sqlcipher command line tool, as described here:
http://sqlcipher.net/introduction/
Once you have done this, you should run the command like this:
$ ./sqlcipher sqlTest.sqlite
or
$ /full/path/to/sqlcipher/sqlcipher sqlTest.sqlite
On unix systems, if you don't provide an explicit path for a command, the system will look for the program in $PATH. On OSX, the system ships with a sqlite3 command, so you've probably been using that instead of the version compiled with SQLCipher. Please let us know if that resolves the problem. Thanks!
I want to pipe the output of a SQLite query. With MySQL, I would do mysql --execute "MYQUERY". How can I achieve the same thing with SQLite?
The optional second argument to the sqlite3 command is SQL to execute. So sqlite3 path/to/my/db "MYQUERY" does it.