I have to move words table's data to another tables.
For example words table is :
------------------------------
| word | type |
|------------------|---------|
| car | NA |
| home | NA |
| question | PR |
------------------------------
I have to move this data by length . For example , car's length is 3 , and car will move to 3-char table (with type column). And question will moved to 8-char .
How can i do it with SQL commands .
Sort of an incomplete question, but something like this might help point you in the right direction:
INSERT INTO words_3char SELECT word FROM all_words WHERE LENGTH(word)=3;
DELETE FROM all_words WHERE LENGTH(word)=3;
I'm not going to ask why you need to do all this moving around, but I'm not sure its a good idea. Assuming it is, take a look at the Length() function for mysql and then try something like this.
Insert into table_Char3(Word) Values (
Select Word from Words where Length(word) = 3)
You can move them to new tables like this
create table word1char as select word from words where length(trim(word)) = 1
..
create table word3chars as select word from words where length(trim(word)) = 3
Related
I have the following table:
postgres=# \d so_rum;
Table "public.so_rum"
Column | Type | Collation | Nullable | Default
-----------+-------------------------+-----------+----------+---------
id | integer | | |
title | character varying(1000) | | |
posts | text | | |
body | tsvector | | |
parent_id | integer | | |
Indexes:
"so_rum_body_idx" rum (body)
I wanted to do phrase search query, so I came up with the below query, for example:
select id from so_rum
where body ## phraseto_tsquery('english','Is it possible to toggle the visibility');
This gives me the results, which only match's the entire text. However, there are documents, where the distance between lexmes are more and the above query doesn't gives me back those data. For example: 'it is something possible to do toggle between the. . . visibility' doesn't get returned. I know I can get it returned with <2> (for example) distance operator by giving in the to_tsquery, manually.
But I wanted to understand, how to do this in my sql statement itself, so that I get the results first with distance of 1 and then 2 and so on (may be till 6-7). Finally append results with the actual count of the search words like the following query:
select count(id) from so_rum
where body ## to_tsquery('english','string & string . . . ')
Is it possible to do in a single query with good performance?
I don't see a canned solution to this. It sounds like you need to use plainto_tsquery to get all the results with all the lexemes, and then implement your own custom ranking function to rank them by distance between the lexemes, and maybe filter out ones with the wrong order.
I have a database of industry-specific terms, each of which may have zero or more synonyms. Users of the system can search for terms by keyword and the results should include any term that contains the keyword or that has at least one synonym that contains the keyword. The result should then include the term and ONLY ONE of the matching synonyms.
Here's the setup... I have a term table with 2 fields: id and term. I also have a synonym table with 3 fields: id, termId, and synonym. So there would data like:
term Table
id | term
-- | -----
1 | dog
2 | cat
3 | bird
synonym Table
id | termId | synonym
-- | ------ | --------
1 | 1 | canine
2 | 1 | man's best friend
3 | 2 | feline
A keyword search for (the letter) "i" should return the following as a result:
id | term | synonym
-- | ------ | --------
1 | dog | canine <- because of the "i" in "canine"
2 | cat | feline <- because of the "i" in "feline"
3 | bird | <- because of the "i" in "bird"
Notice how, even though both "dog" synonyms contain the letter "i", only one was returned in the result (doesn't matter which one).
Because I need to return all matches from the term table regardless of whether or not there's a synonym and I need no more than 1 matching synonym, I'm using an OUTER APPLY as follows:
<!-- language: sql -->
SELECT
term.id,
term.term,
synonyms.synonym
FROM
term
OUTER APPLY (
SELECT
TOP 1
term.id,
synonym.synonym
FROM
synonym
WHERE
term.id = synonym.termId
AND synonym.synonym LIKE #keyword
) AS synonyms
WHERE
term.term LIKE #keyword
OR synonyms.synonym LIKE #keyword
There are indexes on term.term, synonym.termId and synonym.synonym. #Keyword is always something like '%foo%'. The problem is that, with close to 50,000 terms (not that much for databases, I know, but...), the performance is horrible. Any thoughts on how this can be done more efficiently?
Just a note, one thing I had thought to try was flattening the synonyms into a comma-delimited list in the term table so that I could get around the OUTER APPLY. Unfortunately though, that list can easily exceed 900 characters which would then prevent SQL Server from adding an index to that column. So that's a no-go.
Thanks very much in advance.
You've got a lot of unnecessary logic in there. There's no telling how SQL server is creating an execution path. It's simpler and more efficient to split this up into two separate db calls and then merge them in your code:
Get matches based on synonyms:
SELECT
term.id
,term.term
,synonyms.synonym
FROM
term
INNER JOIN synonyms ON term.termId = synonyms.termId
WHERE
synonyms.synonym LIKE #keyword
Get matches based on terms:
SELECT
term.id
,term.term
FROM
term
WHERE
term.term LIKE #keyword
For "flattening the synonyms into a comma-delimited list in the term table: - Have you considered using Full Text Search feature? It would be much faster even when your data goes on becoming bulky.
You can put all synonyms (as comma delimited) in "synonym" column and put full text index on the same.
If you want to get results also with the synonyms of the words, I recommend you to use Freetext. This is an example:
SELECT Title, Text, * FROM [dbo].[Post] where freetext(Title, 'phone')
The previous query will match the words with ‘phone’ by it’s meaning, not the exact word. It will also compare the inflectional forms of the words. In this case it will return any title that has ‘mobile’, ‘telephone’, ‘smartphone’, etc.
Take a look at this article about SQL Server Full Text Search, hope it helps
My table is stud.
+-----+------+-------+
| no | name | grade |
+-----+------+-------+
| 101 | naga | A |
| 102 | raj | A |
| 103 | john | A |
+-----+------+-------+
The query I'm using is:
SELECT * FROM stud WHERE no = 101 AND grade = 'A'.
If am using single record buffering, how much data is being stored in the buffer area?
This query doesn't do anything. There is no "into" clause. meaning it wont store anything selected.
You are probably looking to do something like this....
SELECT * FROM stud into wa_stud WHERE no = 101 AND grade = 'A'.
"processing of each single row is performed here
endselect.
or perhaps something like this, where only 1 row (the first rows ordered by primary key) is selected...
select single * from stud into wa_stud where no = 101 and grade = 'A' .
or perhaps you want everything brought in to a table, meaning number and grade does not include the full primary key.
select * from stud into table it_stud where no = 101 and grade = 'A'.
this is from ABAP Keyword documentation in SE38:
SAP Buffer - Single Record Buffering
Only those rows in the table are buffered that are actually accessed.
This requires less space in the buffer than when using generic or full
buffering. On the other hand, more administration work is required and
significantly more direct database accesses.
So since your query returns a single record (based on the data you displayed) it should just get one row and hold in the buffer.
I'd suggest looking at SAP help and Google - also have a look at SELECT SINGLE and incompletely specified keys - there used to be a problem with the buffer being bypassed in some situations - have a read for reference.
My client wants the possibility to match a set of data against an array of regular expressions, meaning:
table:
name | officeId (foreignkey)
--------
bob | 1
alice | 1
alicia | 2
walter | 2
and he wants to do something along those lines:
get me all records of offices (officeId) where there is a member with
ANY name ~ ANY[.*ob, ali.*]
meaning
ANY of[alicia, walter] ~ ANY of [.*ob, ali.*] results in true
I could not figure it out by myself sadly :/.
Edit
The real Problem was missing form the original description:
I cannot use select disctinct officeId .. where name ~ ANY[.*ob, ali.*], because:
This application, stored data in postgres-xml columns, which means i do in fact have (after evaluating xpath('/data/clients/name/text()'))::text[]):
table:
name | officeId (foreignkey)
-----------------------------------------
[bob, alice] | 1
[anthony, walter] | 2
[alicia, walter] | 3
There is the Problem. And "you don't do that, that is horrible, why would you do it like this, store it like it is meant to be stored in a relation database, user a no-sql database for Document-based storage, use json" are no options.
I am stuck with this datamodel.
This looks pretty horrific, but the only way I can think of doing such a thing would be a hybrid of a cross-join and a semi join. On small data sets this would probably work pretty well. On large datasets, I imagine the cross-join component could hit you pretty hard.
Check it out and let me know if it works against your real data:
with patterns as (
select unnest(array['.*ob', 'ali.*']) as pattern
)
select
o.name, o.officeid
from
office o
where exists (
select null
from patterns p
where o.name ~ p.pattern
)
The semi-join helps protect you from cases where you have a name like "alicia nob" that would meet multiple search patterns would otherwise come back for every match.
You could cast the array to text.
SELECT * FROM workers WHERE (xpath('/data/clients/name/text()', xml_field))::text ~ ANY(ARRAY['wal','ant']);
When casting a string array into text, strings containing special characters or consisting of keywords are enclosed in double quotes kind of like {jimmy,"walter, james"} being two entries. Also when matching with ~ it is matched against any part of the string, not the same as LIKE where it's matched against the whole string.
Here is what I did in my test database:
test=# select id, (xpath('/data/clients/name/text()', name))::text[] as xss, officeid from workers WHERE (xpath('/data/clients/name/text()', name))::text ~ ANY(ARRAY['wal','ant']);
id | xss | officeid
----+-------------------------+----------
2 | {anthony,walter} | 2
3 | {alicia,walter} | 3
4 | {"walter, james"} | 5
5 | {jimmy,"walter, james"} | 4
(4 rows)
I have some table 'TableName' like Id,Name:
1 | something
2 | _something
3 | something like that
4 | some_thing
5 | ...
I want to get all rows from this table where name containes 'some'.
I have 2 ways:
SELECT * FROM TableName WHERE Name like '%some%'
Result is table :
1 | something
2 | _something
3 | something like that
4 | some_thing
But if I use CONTAINS function
SELECT * FROM TableName WHERE CONTAINS(Name,'"*some*"')
I get only
1 | something
3 | something like that
What should I do to make CONTAINS function work properly?
The last time I looked (admittedly SQL Server 2000) CONTAINS didn't support wildcard matching at the beginning of words, only at the end. Also, you might need to check your noise files to see if the "_" character is being ignored.
Also see
How do you get leading wildcard full-text searches to work in SQL Server?
http://doc.ddart.net/mssql/sql70/ca-co_15.htm
If you read this article you will see that * means prefix this means that word must start with this, but like means the word contains key phrase.
Best Regards,
Iordan
Try this:
SELECT * FROM TableName WHERE CONTAINS(Name,'some')