pg-promise creating column error - node.js

var name = req.body.name;
db.any('alter table "houseList" add $1 text', [name])
I tried to add a new column to database host on heroku using the above code in nodejs but I keep getting this error :
error: syntax error at or near "'haha'"
'haha' is the value inside name, anyone have any idea what is wrong?

You are using invalid escaping for the column name, as a regular string variable.
Any schema/table/column name are referred to as SQL Names, and must be escaped using "".
Within pg-promise that means you must use its SQL Names support, with :name: or ~ modifier.
db.any('alter table "houseList" add $1:name text', [name])
or
db.any('alter table "houseList" add $1~ text', [name])
Also, if you sure that you are only using simple names, i.e. no white spaces, no capitals, then you can use the name directly, unescaped, which means using the Raw Text, via modifier :raw or ^. But generally, it is not recommended, i.e. escaping the names is recommended as safer ;)

Related

Databricks Concatenation Issue

As community member called Saideep help with an coding issue I had here
I have attempted to modify the code to search for values with without www (after removing either http or https) and prepending it to a field value.
So, at the moment, my code does the following:
You can see from the image, that code successfully removes https:// and http, but it fails to prepend the values with www in the field newwebsite_url when doesn't exists in the homepage_url field
For example movingahead.com should appear as www.movingahead.com in newwebsite_url
My code is as follows:
SELECT tt.homepage_url
,concat(iff(left(v1.RightString, 4)='www.', null, 'www.')) as addwww , LEFT(v1.RightString,COALESCE(NULLIF(CHARINDEX('/',v1.RightString)-1,-1),150)) as newwebsite_url
FROM basecrmcbreport.organizations tt
inner join (select (SUBSTRING(homepage_url,CHARINDEX('//',homepage_url)+2,150)) from basecrmcbreport.organizations)v1(RightString) on tt.homepage_url like concat('%',v1.RightString,'%') escape '|';
I know its a concatenation issue, but not where to fix it.
Any thoughts?
As you suspected, the issue here is with concatenation. When using concat in the query, we have just given the part where taking www. if it is absent and null if it is present.
But we are not concatenating this with the extracted part from URL (instead using it to create new column). To fix this, we have to place the above function value inside concat.
The following is the demonstration of the same using my sample data.
Using the following updated query, I was able to achieve your requirement.
%sql
SELECT tt.homepage_url
,concat(iff(left(v1.RightString, 4)='www.', '', 'www.'),LEFT(v1.RightString,COALESCE(NULLIF(CHARINDEX('/',replace(v1.RightString,'\\','/'))-1,-1),150))) as newwebsite_url
FROM demo tt
inner join (select (SUBSTRING(homepage_url,CHARINDEX('//',homepage_url)+2,150)) from demo)v1(RightString) on tt.homepage_url like concat('%',v1.RightString,'%') escape '|';
NOTE: I have also replaced \ with /. Also, I have used '' (empty string) instead of using null in concat.

Insert values with single quotes in a Postgres table column [duplicate]

I have a table test(id,name).
I need to insert values like: user's log, 'my user', customer's.
insert into test values (1,'user's log');
insert into test values (2,''my users'');
insert into test values (3,'customer's');
I am getting an error if I run any of the above statements.
If there is any method to do this correctly please share. I don't want any prepared statements.
Is it possible using sql escaping mechanism?
String literals
Escaping single quotes ' by doubling them up → '' is the standard way and works of course:
'user's log' -- incorrect syntax (unbalanced quote)
'user''s log'
Plain single quotes (ASCII / UTF-8 code 39), mind you, not backticks `, which have no special purpose in Postgres (unlike certain other RDBMS) and not double-quotes ", used for identifiers.
In old versions or if you still run with standard_conforming_strings = off or, generally, if you prepend your string with E to declare Posix escape string syntax, you can also escape with the backslash \:
E'user\'s log'
Backslash itself is escaped with another backslash. But that's generally not preferable.
If you have to deal with many single quotes or multiple layers of escaping, you can avoid quoting hell in PostgreSQL with dollar-quoted strings:
'escape '' with '''''
$$escape ' with ''$$
To further avoid confusion among dollar-quotes, add a unique token to each pair:
$token$escape ' with ''$token$
Which can be nested any number of levels:
$token2$Inner string: $token1$escape ' with ''$token1$ is nested$token2$
Pay attention if the $ character should have special meaning in your client software. You may have to escape it in addition. This is not the case with standard PostgreSQL clients like psql or pgAdmin.
That is all very useful for writing PL/pgSQL functions or ad-hoc SQL commands. It cannot alleviate the need to use prepared statements or some other method to safeguard against SQL injection in your application when user input is possible, though. #Craig's answer has more on that. More details:
SQL injection in Postgres functions vs prepared queries
Values inside Postgres
When dealing with values inside the database, there are a couple of useful functions to quote strings properly:
quote_literal() or quote_nullable() - the latter outputs the unquoted string NULL for null input.
There is also quote_ident() to double-quote strings where needed to get valid SQL identifiers.
format() with the format specifier %L is equivalent to quote_nullable().
Like: format('%L', string_var)
concat() or concat_ws() are typically no good for this purpose as those do not escape nested single quotes and backslashes.
According to PostgreSQL documentation (4.1.2.1. String Constants):
To include a single-quote character within a string constant, write
two adjacent single quotes, e.g. 'Dianne''s horse'.
See also the standard_conforming_strings parameter, which controls whether escaping with backslashes works.
This is so many worlds of bad, because your question implies that you probably have gaping SQL injection holes in your application.
You should be using parameterized statements. For Java, use PreparedStatement with placeholders. You say you don't want to use parameterised statements, but you don't explain why, and frankly it has to be a very good reason not to use them because they're the simplest, safest way to fix the problem you are trying to solve.
See Preventing SQL Injection in Java. Don't be Bobby's next victim.
There is no public function in PgJDBC for string quoting and escaping. That's partly because it might make it seem like a good idea.
There are built-in quoting functions quote_literal and quote_ident in PostgreSQL, but they are for PL/PgSQL functions that use EXECUTE. These days quote_literal is mostly obsoleted by EXECUTE ... USING, which is the parameterised version, because it's safer and easier. You cannot use them for the purpose you explain here, because they're server-side functions.
Imagine what happens if you get the value ');DROP SCHEMA public;-- from a malicious user. You'd produce:
insert into test values (1,'');DROP SCHEMA public;--');
which breaks down to two statements and a comment that gets ignored:
insert into test values (1,'');
DROP SCHEMA public;
--');
Whoops, there goes your database.
In postgresql if you want to insert values with ' in it then for this you have to give extra '
insert into test values (1,'user''s log');
insert into test values (2,'''my users''');
insert into test values (3,'customer''s');
you can use the postrgesql chr(int) function:
insert into test values (2,'|| chr(39)||'my users'||chr(39)||');
When I used Python to insert values into PostgreSQL, I also met the question: column "xxx" does not exist.
The I find the reason in wiki.postgresql:
PostgreSQL uses only single quotes for this (i.e. WHERE name = 'John'). Double quotes are used to quote system identifiers; field names, table names, etc. (i.e. WHERE "last name" = 'Smith').
MySQL uses ` (accent mark or backtick) to quote system identifiers, which is decidedly non-standard.
It means PostgreSQL can use only single quote for field names, table names, etc. So you can not use single quote in value.
My situation is: I want to insert values "the difference of it’s adj for sb and it's adj of sb" into PostgreSQL.
How I figure out this problem:
I replace ' with ’, and I replace " with '. Because PostgreSQL value does not support double quote.
So I think you can use following codes to insert values:
insert into test values (1,'user’s log');
insert into test values (2,'my users');
insert into test values (3,'customer’s');
If you need to get the work done inside Pg:
to_json(value)
https://www.postgresql.org/docs/9.3/static/functions-json.html#FUNCTIONS-JSON-TABLE
You must have to add an extra single quotes -> ' and make doubling quote them up like below examples -> ' ' is the standard way and works of course:
Wrong way: 'user's log'
Right way: 'user''s log'
problem:
insert into test values (1,'user's log');
insert into test values (2,''my users'');
insert into test values (3,'customer's');
Solutions:
insert into test values (1,'user''s log');
insert into test values (2,'''my users''');
insert into test values (3,'customer''s');

DBeaver DB2 variable usage

I'm currently trying to add some dbeaver parameters to my script.
The simple SQL Looks like this:
SELECT * FROM CONTRACT WHERE CONTRACT_NUMER = :CONTRACTNUMBER;
Now, when I run the Statement, dbeaver prompts me for the contract number which I type in. (The column is a varchar) Unfortunately it only works, if I put my Input Parameter in single Apostrophe.
When I just type in the string the following error message appears:
LE123990123 IS NOT VALID IN THE CONTEXT WHERE IT IS USED. SQLCODE=-206, SQLSTATE=42703, DRIVER=4.19.49
How do I make this Parameter being treated as a String? DB2 11 is in use here.
You MUST put quote for CHAR and VARCHAR variable.
If you look bottom in BIND PARAMETERS WINDOWS, you can read:
"Use Tab to switch. String values must be quoted. You can use expression in values"

U-SQL Error - Change the identifier to use at least one lower case letter

I am fairly new to U-SQL and trying to run a U-SQL script in Azure Data Lake Analytics to process a parquet file using the Parquet extractor functionality. I am getting the below error and I don't find a way to get around it.
Error - Change the identifier to use at least one lower case letter. If that is not possible, then escape that identifier (for example: '[ACTIVITY]'), or embed it in a CSHARP() block (e.g CSHARP(ACTIVITY)).
Unfortunately all the different fields generated in the Parquet file are capitalized and I don't want to to escape these identifiers. I have tried if I could wrap the identifier with CSHARP block and it fails as well (E_CSC_USER_RESERVEDKEYWORDASIDENTIFIER: Reserved keyword CSHARP is used as an identifier.) Is there anyway I could extract the parquet file? Thanks for your help!
Code Snippet:
SET ##FeaturePreviews = "EnableParquetUdos:on";
#var1 =
EXTRACT ACTIVITY string,
AUTHOR_NAME string,
AFFLIATION string
FROM "adl://xxx.azuredatalakestore.net/Abstracts/FY2018_028"
USING Extractors.Parquet();
#var2 =
SELECT *
FROM #var1
ORDER BY ACTIVITY ASC
FETCH 5 ROWS;
OUTPUT #var2
TO "adl://xxx.azuredatalakestore.net/Results/AbstractsResults.csv"
USING Outputters.Csv();
Based on your description you try to say
EXTRACT ALLCAPSNAME int FROM "/data.parquet" USING Extractors.Parquet();
In U-SQL, we reserve all caps identifiers so we can add new keywords in the future without invalidating old scripts.
To work around, you just have to quote the name (escape it) like in any other SQL dialect:
EXTRACT [ALLCAPSNAME] int FROM "/data.parquet" USING Extractors.Parquet();
Note that this is not changing the name of the field. It is just the syntactic way to address the field.
Also note, that in most SQL communities, it is considered a best practice to always quote identifiers to avoid reserved keyword clashes.
If all fields in the Parquet file are all caps, you will have to quote them all... In a future update you will be able to say EXTRACT * FROM … for Parquet (and Orc) files, but you still will need to quote the columns when you refer to them explicitly.

How do I make a WHERE clause with SQLalchemy to compare to a string?

Objective
All I am trying to do is retrieve a single record from a specific table where the primary key matches. I have a feeling I'm greatly over complicating this as it seems to be a simple enough task. I have a theory that it may not know the variable value because it isn't actually pulling it from the Python code but instead trying to find a variable by the same name in the database.
EDIT: Is it possible that I need to wrap my where clause in an expression statement?
Attempted
My Python code is
def get_single_record(name_to_search):
my_engine = super_secret_inhouse_engine_constructor("sample_data.csv")
print("Searching for " + name_to_search)
statement = my_engine.tables["Users"].select().where(my_engine.tables["Users"].c.Name == name_to_search)
# Print out the raw SQL so we can see what exactly it's checking for
print("You are about to run: " + str(statement))
# Print out each result (should only be one)
print("Results:")
for item in my_engine.execute(statement):
print(item)
I tried hard coding a string in its place.
I tried using like instead of where.
All to the same end result.
Expected
I expect it to generate something along the lines of SELECT * FROM MyTable WHERE Name='Todd'.
Actual Result
Searching for Todd
STATEMENT: SELECT "Users"."Name", ...
FROM "Users"
WHERE "Users"."Name" = ?
That is an actual question mark appearing my statement, not simply my own confusion. This is then followed by it printing out a collection of all the records from the table, as though it successfully matched everything.
EDIT 2: Running either my own hard coded SQL string or the generated query by Alchemy returns every record from the table. I'm beginning to think the issue may be with the engine I've set up not accepting the query.
Why I'm Confused
According to the official documentation and third party sources, I should be able to compare to hardcoded strings and then, by proxy, be able to compare to a variable.

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