My question seems to be quite simple, but I'm worried the answer might actually be somewhat complex. I am trying to perform a simple Select query that behaves like the following.
Here is the code:
SELECT * FROM tbl_tbl WHERE tbl_tbl.colA LIKE '%foo%' OR tbl.tbl.colA LIKE '%oof%' AND
tbl_tbl.colB LIKE '%bar%' OR tbl_tbl.colB LIKE '%rab%'
So I am just searching for 4 strings (2 in each column), and if I find one in each pair, I want to show that entire entry.
Mathematically, it makes quite a bit of sense to me.
I want to do (This OR That) AND (One OR Another) where any combination of This/One, This/Another, etc. passes the expression.
Pretty simple right?
How do I tell SQL to work right (you know, like that obscure way in my mind)?
Currently, I'm getting entries out of my table where only 1 of the column disciplines match, and that's not giving me the specificity of the priority I am looking for.
You would express it using parentheses and boolean logic in the where clause:
SELECT *
FROM tbl_tbl t
WHERE (t.colA LIKE '%foo%' OR t.colA LIKE '%oof%') AND
(t.colB LIKE '%bar%' OR t.colB LIKE '%bar%');
Do note that this is based on your example in the question. The second clause of the AND has two conditions that are the same. I assume this is a typo in the question, but not knowing the right pattern, I've left it in the answer.
Related
Is there any difference between the 2 syntaxes?
SELECT [dbo].[Employees].[FirstName]
FROM [dbo].[Employees]
WHERE [dbo].[Employees].[FirstName] NOT LIKE '[a-c]%';
SELECT [dbo].[Employees].[FirstName]
FROM [dbo].[Employees]
WHERE [dbo].[Employees].[FirstName] LIKE '[^a-c]%';
One will match an empty string. The other will not.
And for more complex patterns, there's almost always a difference. Especially if you start exploiting double-negatives e.g. if you have a NOT LIKE '%[^0-9]%' pattern, there's no simple way to reduce it.
Looking at this link: SQL SELECT LIKE
What if you were searching for a name that starts with H and ends with dinger?
Would I use:
SELECT NAME LIKE
'H_dinger'
'H...dinger' or
'H%dinger' ?
I'll assume H_dinger would think there is only 1 character in between, but I don't know what it is -- so I'm searching for it.
H...dinger isn't valid.
And H%dinger seems like it would check it all, but on the site, that isn't even listed?
You would use %, which is the variable-sized wildcard.
But you need to get the syntax right, such as with:
select NAME from TABLE where NAME like 'H%dinger'
Keep in mind that queries using % may be a performance issue (depending on how it's used and the DBMS engine). It can prevent the efficient use of indexes to speed up queries. It probably won't matter for small tables but it's something to keep in mind if you ever need to scale.
Apologies for the somewhat confusing Title, I've been struggling to find an answer to my question, partly because it's hard to concisely describe it in the title line or come up with a good search string for it. Anyhoooo, here's the problem I'm facing:
Short version of the question is:
How can I write the following (invalid but understandable SQL) in valid SQL understood by Oracle:
select B.REPLACER as COL, A.* except A.COL from A join B on a.COL = B.COL;
Here's the long version (if you already know what I want from reading the short version, you don't need to read this :P ):
My (simplified) task is to come up with service that massages a table's data and provide it as a sub-query. The table has a lot of columns (a few dozens or more), and I am stuck with using "select *" rather than explicitly listing out all columns one by one, because new columns may be added to or removed from the table without me knowing, although my downstream systems will know and adjust accordingly.
Say, this table (let's call it Table A from now on) has a column called "COL", and we need to replace the values in that COL with the value in the REPLACER column of table B where the two COL value matches.
How do I do this? I cannot rename the column because the downstream systems expect "COL"; I cannot do without the "expect A.COL" part because that would cause the sql to be ambiguous.
Appreciate your help, almighty StackOverflow
Ray
You can either use table.* or table.fieldName.
There is no syntax available for table.* (except field X).
This means that you can only get what you want by explicitly listing all of the fields...
select
A.field1,
A.field2,
B.field3,
A.field4,
etc
from
A join B on a.COL = B.COL;
This means that you may need to re-model your data so as to ensure you don't keep getting new fields. OR write dynamic sql. Interrogate the database to find out the column names, use code to write a query as above, and then run that dynamically generated query.
Try this: (not tested)
select Case B.COL
when null then A.COL
else B.REPLACER
end as COLAB, A.*
from A left join B on A.COL = B.COL;
This should get the B.REPLACER when exists B.COL = A.COL, you can add more column in the select (like sample col1, col2) or use A.* (change COL into COLAB to make it distinguish with A.COL in A.*) .
Like said before, you cannot specify in regular sql which column not to select. you could write a procedure for that, but it would be quite complex, because you would need to return a variable table type. Probably something with refcursor magic stuff.
The closest I could come up with is joining with using. This will give you the column col in the first field once and for the rest all columns in a and b. So not what you want basically. :)
select *
from a
join b using (col)
Let's start from first principles. select * from .... is a bug waiting to happend and has no place in production code. Of course everybody uses it because it entails less typing but that doesn't make it a good practice.
Beyond that, the ANSI SQL standard doesn't support select * except col1 from .... syntax. I know a lot of people wish it would but it doesn't.
There are a couple of ways to avoid excessive typing. One is to generate the query by selecting from data dictionary, using one of the views like USER_TAB_COLUMNS. It is worth writing the PL?SQL block to do this if you need lots of queries like this.
A simpler hack is to use the SQL*Plus describe to list out the structure of table A; cut'n'paste it into an IDE which supports regular expressions and edit the columns to give you the query's projection.
Both these options might strike you as labourious but frankly either workaround (and especially the second) would have taken less effort than asking StackOverflow. You'll know better next time.
I am using a SQL Server database, and I am storing Malayalam names in my tables. I just want to write a query for filtering names using some Malayalam words.
SELECT * FROM table WHERE mal_Name LIKE '#word%'
#word contain Malayalam words.
How can I achieve this? Please share any ideas.
EDIT
This is my table, rm_Malayalam_name contains Malayalam name. And my Query is
SELECT *
FROM Purchase.tblRawMaterials
WHERE rm_malayalam_name LIKE '%കദളിപഴം%'
It doesn't work. The entry is there but while executing this query nothing is shown
Do you mean you want to do something like SELECT * FROM table WHERE mal_Name LIKE '%'+#word+'%'
This will work if #Word is a single word, however if you want to take in multiple words you are going to need something a bit more complex.
UPDATE:
Having seen your new edits I would suspect that the reason it is not selecting is due to the encoding
Try SELECT * FROM table WHERE mal_Name LIKE N'%'+#word+'%'
or
select * from Purchase.tblRawMaterials where rm_malayalam_name like N'%കദളിപഴം%'
I'd suggest reading up on SQL's full-text search It will almost certainly be more efficient than LIKE '%word%'
How many words will you be searching on? How big is the column? These factors might influence what the best option is.
I'm working on a faceted search in Coldfusion and SQL. I've tried creating a query like this:
SELECT * FROM Turbos
WHERE
PartNumber LIKE '%#trim(SearchCriteria)#%'
OR PartDescription LIKE '%#trim(SearchCriteria)#%'
AND (PumpingSpeed BETWEEN #minimum# AND #URL.speed#)
AND InletFlange LIKE '#URL.inlet#'
AND Bearing LIKE '#URL.bearing#'
AND Condition LIKE '#URL.condition#'
The problem is the server is returning rows that don't contain EVERY piece of data I'm supplying. How can I select ONLY those rows which contain all the criteria?
just wrap the OR bit in brackets:
(PartNumber LIKE '%#trim(SearchCriteria)#%' OR PartDescription LIKE '%#trim(SearchCriteria)#%') AND...
at the moment you have A or B and C which is being read as A or (B and C). You want (A or B) and C.
And make sure you use cfqueryparam as suggested above.
Just a guess really, but change
...'%#trim(SearchCriteria)#%' OR
PartDescription ...
to
...'%#trim(SearchCriteria)#%' AND
PartDescription ...
edit
or are you saying some have null values?
post comment edit
Imagine for example that InletFlange is empty for your part, and the user didn't put it in their search.
Then InletFlange LIKE '#URL.inlet#' will compare "" LIKE "", which is of course true, so the product shows up.
There are many ways to solve this. For example
Default the search criteria to "N/A" or something
Default the column in the database in a similar fashion.
something along the lines of AND NOT ISNULL(InletFlange,'')=='' for each criteria
Okay, I found the answers:
Leigh: +1 to clarifying the question. (It is
unlikely this has any bearing on the
results, but what is the point of
using LIKE without wildcards "%"? If
it is an equality comparison you are
after, just use equals ie ... AND
Condition = '#URL.condition#' )
You were quite right, I was missing the percent symbols in my LIKE comparisons (DUH!). I removed them earlier thinking they were the problem, but they weren't, this was:
Aiden: just wrap the OR bit in brackets:
(PartNumber LIKE '%#trim(SearchCriteria)#%' OR PartDescription LIKE '%#trim(SearchCriteria)#%') AND...
Thank you Aiden!
While this isnt an answer to your question - you might want to consider using a dedicated search solution such as Solr (which is included with CF9). Its a more powerful fulltext solution than just raw SQL and includes facetting