Postgres 14.
Are there any forbidden characters in aliasing columns?
I want to see '$' in column's name and it doesn't work. How can I get it done? Is there any magic function that could do that for me?
SELECT
id,
currency as '$',
available
from f_total
ORDER BY
id DESC
;
gives:
ERROR: syntax error at or near "'$'"
LINE 3: currency as '$',
^
SQL state: 42601
Character: 27
Same story when I use '€', '!', '<'. I expected it to be not executed against all syntax-verificators - it's just an insignificant string to be used on output ...
How to make my column to be named with such name?
Use double-quotes (") for identifiers:
currency AS "$"
See:
Are PostgreSQL column names case-sensitive?
Every string is allowed once double-quoted (with contained double-quotes doubled up). Doesn't mean it's a good idea to use "$" as identifier. It isn't.
In oracle sql when I am trying to get the output for the below, it is throwing error.
select city,id from station where id % 2 = 0;
Error:
ORA-00911: invalid character
00911. 00000 - "invalid character"
*Cause: identifiers may not start with any ASCII character other than
letters and numbers. $#_ are also allowed after the first
character. Identifiers enclosed by doublequotes may contain
any character other than a doublequote. Alternative quotes
(q'#...#') cannot use spaces, tabs, or carriage returns as
delimiters. For all other contexts, consult the SQL Language
Reference Manual.
The % operator for modulo is not supported in Oracle. You would need to use function mod():
select city,id from station where mod(id, 2) = 0;
Demo on DB Fiddle
I have a Classes table which is as follows:
Classes(classid, dept_code, course#, sect#, year, semester, limit, class_size, room, TA_B#)
The qeustion is:
Find the classid, dept_code and course# of each undergraduate class (i.e., course# < 500) that was offered in
Spring 2017. For each such class, also list the number of seats available (computed by limit – class_size)
under the header “seats_available”.
I tried this simple approach:
select classes.classid, classes.dept_code, classes.course#,
classes.limit-classes.class_size as'seats_available'
from classes
where limit>class_size and year='2017' and semester='Spring'and course# < 500;
0
But I am getting an error:
ERROR at line 1:
ORA-00923: FROM keyword not found where expected
What am I missing? This error will go if I remove this code of line:classes.limit-classes.class_size as'seats_available'
I am using Oracle database
In the SQL standard identifiers need to be enclosed in double quotes ("). And the Oracle database complies with the standard there.
Single quotes (') are for character constants e.g. as you did in semester='Spring', they can not be used for identifiers like column names, table names or a column alias.
So you need to use:
classes.limit-classes.class_size as "seats_available"
You don't actually need the double quotes though, as your identifier does not contain any invalid characters, so
classes.limit-classes.class_size as seats_available
will work just as well
Unrelated, but: numbers should not be enclosed in single quotes 2017 is a number constant, '2017' is a string constant. So you should use where year = 2017 instead
In my SQL Server database table there is one variable with spaces. I am trying to write one query in the RODBC::sqlQuery function but I am not able to use this variable.
I tried to use single quotes but that doesn't work.
I tried to use paste option and create one string for query but even that also did not work.
Following is the query:
p5 <-sqlQuery(con, 'SELECT
a.region,
a.Country,
a.Qtr_ID,
Net_VAT AS Variable_Type,
"Printing" AS [External_Segment],
SUM(a.VR_Value) AS Value
FROM
(SELECT
d.region,
d.Country,
dt.Qtr_ID,
SUM([Actuals YTD] / 1000000) AS VR_Value
FROM ZOOM_DATAMART.dbo.[New_BalSheet_Fact] a
INNER JOIN [dbo].[Buss_Area_Dim_V] b
ON a.Bus_Area_ID = b.Bus_Area_ID
AND b."GBU External Segment Description" = "Printing"
INNER JOIN [dbo].[BSR_Header_GA_Dim_V] c
ON a.BSR_HEADER_GA_KEY = c.BSR_HEADER_GA_KEY
AND c.[Group Account Identifier] IN (1291, 2150, 2151,
2152, 2153, 2154)
INNER JOIN [dbo].[Legal_Company_Dim_V] d
ON a.Legal_Cmp_Key = d.Legal_Cmp_Key
INNER JOIN dbo.Date_Dim dt
ON a.Date_key = dt.Date_key
AND dt.Max_month_Flag = 1
GROUP BY d.region,
dt.Qtr_ID,
d.Country
) a
GROUP BY a.region,
a.Country,
a.Qtr_ID)
The issue is happening with "GBU External Segment Description". I get following error:
chr [1:4] "42S22 207 [Microsoft][ODBC SQL Server Driver][SQL Server]Invalid column name 'Printing'." ...
Then I removed double quote from printing but still for "GBU External Segment Description" it doesn't accept and throws following error:
chr [1:3] "42000 102 [Microsoft][ODBC SQL Server Driver][SQL Server]Incorrect syntax near 'GBU External Segment Description'." ...
The error is not with the fieldname I believe, but with the varchar constant that you are looking for. You should be using single quotes, not double.
This:
a.Bus_Area_ID = b.Bus_Area_ID and b."GBU External Segment Description"= "Printing"
Should be this:
a.Bus_Area_ID = b.Bus_Area_ID and b.[GBU External Segment Description] = 'Printing'
Generally, String values in SQL are not wrapped in double quotes, but single quotes.
Also, in your first line:
p5 <-sqlQuery(con,'SELECT a.region,a.Country,a.Qtr_ID,Net_VAT as Variable_Type,"Printing" as [External_Segment]
Are you trying to output Printing as a constant result from this query? If so, and it is not a field name, then you should also wrap that in ' single quotes, not double. That is likely what is cauing the first error that you are seeing.
So that it becomes:
p5 <-sqlQuery(con,'SELECT a.region,a.Country,a.Qtr_ID,Net_VAT as Variable_Type,'Printing' as [External_Segment]
The previous comment on your question about wrapping fieldnames with [] is correct, you should use [] the square brackets to wrap field names with spaces in them.
This query should work:
p5 <-sqlQuery(con,'SELECT a.region,a.Country,a.Qtr_ID,Net_VAT as Variable_Type,\'Printing\' as [External_Segment]
,SUM(a.VR_Value) as Value
from
(SELECT d.region,d.Country,dt.Qtr_ID
,sum([Actuals YTD]/1000000) as VR_Value
FROM ZOOM_DATAMART.dbo.[New_BalSheet_Fact] a
inner join [dbo].[Buss_Area_Dim_V] b
on
a.Bus_Area_ID = b.Bus_Area_ID and b.[GBU External Segment Description]= \'Printing\'
inner join [dbo].[BSR_Header_GA_Dim_V] c
on
a.BSR_HEADER_GA_KEY= c.BSR_HEADER_GA_KEY and c.[Group Account Identifier] IN (1291,2150,2151,2152,2153,2154)
inner join [dbo].[Legal_Company_Dim_V] d
on a.Legal_Cmp_Key = d.Legal_Cmp_Key
inner join dbo.Date_Dim dt
on a.Date_key = dt.Date_key and dt.Max_month_Flag = 1
group by d.region,
dt.Qtr_ID
,d.Country
) a
Group BY
a.region
,a.Country
,a.Qtr_ID')
Hope this helps.
Overall, your main issue involves confusing and conflating identifiers and literals. As information, in ANSI-SQL (the formal, industry standard of the SQL language that most RDBMS's adhere to including SQL Server, Oracle, Postgres, etc.), single quotes and double quotes are used for different purposes.
Single quotes are used to enclose string literals within char, varchar, text data type columns such as 'Printing'. Your first error message actually points to Printing as the MSSQL engine attempted to search for a column name since you wrapped this value in double quotes.
Double quotes are used for identifiers including column names and table names such as c."Group Account Identifier". Your second error points to the use of qualifying a table alias, c, to a literal value since you wrapped this value in single quotes.
Below are few common uses of this type:
Double quotes explicitly impose case sensitivity. Specifically, when you wrap column names in double quotes, the same characters in camel case, lower case, and upper case render different values and an error will raise if they do not align to the actual case used in table creation (i.e., tbl."ColumnName" <> tbl."COLUMNNAME").
Double quotes help escape special characters (!##$%^&*?) and spaces. Hence, you can use c."Group Account Identifier" to identify the column. However, some RDBMS's have their own escaping symbols for special characters and spaces which are not ANSI standards. For example, SQL Server can use square brackets [...]; MySQL can use backticks `...`; SQLite and MS Access can use both.
Double quotes help escape reserved words of the current RDBMS which for you includes SQL Server's list. However, it is advised not to use such words, special characters, accents, or spaces in column names.
With that said, like any rule there are exceptions. Both types of quotes may be used with string literals for some databases that allow non-ANSI modes. However, this is not advised to do in practice. Unlike most programming languages such as R, Python, PHP, Perl, XSLT that can swap these two types of quotes for string values, SQL at its base core is not one of them.
Therefore, use either quote type accordingly:
'Printing' AS "External_Segment",
...
AND b."GBU External Segment Description" = 'Printing'
...
AND c."Group Account Identifier" IN (1291, 2150, 2151, 2152, 2153, 2154)
Or
'Printing' AS [External_Segment],
...
AND b.[GBU External Segment Description] = 'Printing'
...
AND c.[Group Account Identifier] IN (1291, 2150, 2151, 2152, 2153, 2154)
I have a table and one of the columns is named CAST. How can I access this column. I've tried
Select [Cast] AS cast_s FROM tablename without success, Can I use this name or must I reimport all my data into bigquery?
I know that cast is a function. This is the error message:
Error:
Encountered " "CAST" "Cast "" at line 10, column 63. Was expecting: < E O F > (EOF has no spaces, markdown makes it disappear)
Thanks.
The lexical rules for BQ use backticks for this purpose:
select `cast` as cast_s
from tablename;
The documentation is here.
For BigQuery Legacy SQL you CAN use square brackets
SELECT [cast] as cast_s
FROM tablename
From documentation
You can use square brackets to escape reserved words so that you can
use them as field name and aliases. For example, if you have a column
named "prefix", which is a reserved word in BigQuery syntax, the
queries referencing that field will fail with obscure error messages
unless you escape it with square brackets:
SELECT [prefix] FROM ...