When I try to make an __iregex call using the regular expression '^(\\. \\.)$' I get:
DataError: invalid regular expression: parentheses () not balanced
I am using PSQL backend so the django documentation states that the equivalent SQL command should be
SELECT ... WHERE title ~* '^(\\. \\.)$';
When I run this query manually through the PSQL command line it works fine. Is there some bug with Django that I don't know about that is causing this to crash?
Edit: Also, it fails for variations of this regular expression, for example
'^(S\\. \\.)$'
'^(\\. S\\.)$'
'^(\\. \\.S)$'
The solution is to replace all " " characters with \s before sending the regexp into __iregex.
Related
I am trying to do a simple regex pattern match in Redshift
I have this code and I get the following error:
REGEXP_COUNT ( "code", '^(?=.{8}$)[A-z]{2,5}[0-9]{3,6}$' )
ERROR: Invalid preceding regular expression prior to repetition operator. The error occured while parsing the regular expression fragment: '^(?>>>HERE>>>=.{8}$)[A-'.
The pattern works fine in testing in python and online checkers I'm guessing its a REGEX language problem. I have checked in PostgreSQL documentation on REGEX to try get help as I can't find much details on actual Redshift.
Thanks,
I'm having an issue matching regular expression in BigQuery. I have the following line of code that tries to identify user agents:
when regexp_contains((cs_user_agent), '^AppleCoreMedia\/1\.(.*)iPod') then "iOS App - iPod"
However, BigQuery doesn't seem to like escape sequences for some reason and I get this error that I can't figure out:
Syntax error: Illegal escape sequence: \/ at [4:63]
This code works fine in a regex validator I use, but BigQuery is unhappy with it and I can't figure out why. Thanks in advance for the help
Use regexp_contains((cs_user_agent), r'^AppleCoreMedia\/1\.(.*)iPod')
I am getting a syntax error in a PostgreSQL query. I am working on a project developed in YII1, I am getting an error
CDbCommand failed to execute the SQL statement: SQLSTATE[42601]:
Syntax error: 7 ERROR: syntax error at or near "s" LINE 1: ...OT NULL
AND sub_heading like '%Women and Children's Voices%'.
As you can see above, I am using the like operator in single quotes, and in the string there is another single quote (Children's). So PostgreSQL is throwing me an error. Please provide me a solution to escape the string.
You can escape a single quote in a string by using another single quote (i.e., '' instead of '. Note that these are two ' characters, not a single " character):
sub_heading LIKE '%Women and Children''s Voices%'
-- Here -----------------------------^
You should use the format function to construct the SQL statement, using the %L placeholder for the pattern.
I solved this problem by replacing the single quote with double quotes using PHP. Here is the code
There is a variable $var with value Women and Children's Voices. I replace that single quote using the str_replace() function.
$var = str_replace("'", "''", $var);
I'm running PostgreSQL 9.4 and are inserting a lot of records into my database. I use the RETURNING clause for further use after an insert.
When I simply run:
... RETURNING my_car, brand, color, contact
everything works, but if I try to use REGEXP_REPLACE it fails:
... RETURNing my_car, brand, color, REGEXP_REPLACE(contact, '^(\+?|00)', '') AS contact
it fails with:
ERROR: invalid regular expression: quantifier operand invalid
If I simply run the query directly in PostgreSQL it does work and return a nice output.
Tried to reproduce and failed:
t=# create table s1(t text);
CREATE TABLE
t=# insert into s1 values ('+4422848566') returning REGEXP_REPLACE(t, '^(\+?|00)', '');
regexp_replace
----------------
4422848566
(1 row)
INSERT 0 1
So elaborated #pozs suggested reason:
set standard_conforming_strings to off;
leads to
WARNING: nonstandard use of escape in a string literal
LINE 1: ...alues ('+4422848566') returning REGEXP_REPLACE(t, '^(\+?|00)...
^
HINT: Use the escape string syntax for escapes, e.g., E'\r\n'.
ERROR: invalid regular expression: quantifier operand invalid
update
As OP author says standard_conforming_strings is on as supposed from 9.1 by default working with psql and is off working with pg-prommise
update from vitaly-t
The issue is simply with the JavaScript literal escaping, not with the
flag.
He elaborates further in his answer
The current value of environment variable standard_conforming_strings is inconsequential here. You can see it if you prefix your query with SET standard_conforming_strings = true;, which will change nothing.
Passing in a regEx string unescaped from the client is the same as using E prefix from the command line: E'^(\+?|00)'.
In JavaScript \ is treated as a special symbol, and you simply always have to provide \\ to indicate the symbol, which is what needed for your regular expressions.
Other than that, pg-promise will escape everything correctly, here's an example:
db.any("INSERT INTO users(name) VALUES('hello') RETURNING REGEXP_REPLACE(name, $1, $2)", ['^(\\+?|00)', 'replaced'])
To understand how the command-line works, prefix the regex string with E:
db.any("INSERT INTO users(name) VALUES('hello') RETURNING REGEXP_REPLACE(name, E$1, $2)", ['^(\\+?|00)', 'replaced'])
And you will get the same error: invalid regular expression: quantifier operand invalid.
The parameterization example in the "SQL Parameters" IPython notebook in the datalab github repo (under datalab/tutorials/BigQuery/) shows how to change the value being tested for in a WHERE clause.
%%sql --module get_data
SELECT *
FROM
[myproject:mydataset.mytable]
WHERE
$query
However, this syntax always seems to insert quotation marks around the parameter. This breaks when I pass parameters that aren't just a simple value:
import gcp.bigquery as bq
query = "(bnf_code LIKE '1202%') OR (bnf_code LIKE '1203%')"
query = bq.Query(get_data, query=query)
print query.sql
This prints an invalid query:
SELECT * FROM [myproject:mydataset.mytable]
WHERE "(bnf_code LIKE '1202%') OR (bnf_code LIKE '1203%')"
Is there any way I can insert values that aren't wrapped in quotation marks?
I'm using the module repeatedly in my code, with variable numbers of OR clauses in the query parameter. So I do need a way to pass in more complicated queries.
Sorry, variables are meant to be simple scalars, or tables, or (soon) lists for use in IN clauses. They are not meant for expressions.
Passing unquoted arguments to SQL modules isn't possible, but it is possible to create a datalabs.data.SQLStatement with straight-up SQL in string form. With that you can use your own, Python-style placeholders to substitute values as you see fit:
import datalab.data._sql_statement as bqsql
statement = bqsql.SqlStatement(
"SELECT some-field FROM %s" % '[your-instance:some-table-name]')
query = bq.Query(statement)
I don't know if they're doing anything special with placeholders or the in-notebook command processing but... well, I didn't see any of that in my (admittedly limited) spelunking.