Ho bisogno di una selezione che restituisca risultati come questo:
SELECT * FROM MyTable WHERE Column1 CONTAINS 'word1 word2 word3'E ho bisogno di tutti i risultati, cioè questo include stringhe con 'word2 word3 word1' o 'word1 word3 word2' o qualsiasi altra combinazione delle tre.
Tutte le parole devono essere nel risultato.
Risposte:
Metodo piuttosto lento, ma funzionante per includere una qualsiasi delle parole:
SELECT * FROM mytable
WHERE column1 LIKE '%word1%'
OR column1 LIKE '%word2%'
OR column1 LIKE '%word3%'
Se hai bisogno di tutte le parole per essere presente, usa questo:
SELECT * FROM mytable
WHERE column1 LIKE '%word1%'
AND column1 LIKE '%word2%'
AND column1 LIKE '%word3%'
Se vuoi qualcosa di più veloce, devi cercare la ricerca full-text, e questo è molto specifico per ogni tipo di database.
word3 word2 word1.
Si noti che se si utilizza LIKEper determinare se una stringa è una sottostringa di un'altra stringa, è necessario evitare i caratteri corrispondenti al modello nella stringa di ricerca.
Se il tuo dialetto SQL supporta CHARINDEX, invece è molto più semplice usarlo:
SELECT * FROM MyTable
WHERE CHARINDEX('word1', Column1) > 0
AND CHARINDEX('word2', Column1) > 0
AND CHARINDEX('word3', Column1) > 0Inoltre, tieni presente che questo e il metodo nella risposta accettata coprono solo la corrispondenza della sottostringa anziché la corrispondenza delle parole. Quindi, ad esempio, la stringa 'word1word2word3'corrisponderebbe comunque.
InStr()invece utilizzareCHARINDEX
CREATE FUNCTION [dbo].[fnSplit] ( @sep CHAR(1), @str VARCHAR(512) )
RETURNS TABLE AS
RETURN (
WITH Pieces(pn, start, stop) AS (
SELECT 1, 1, CHARINDEX(@sep, @str)
UNION ALL
SELECT pn + 1, stop + 1, CHARINDEX(@sep, @str, stop + 1)
FROM Pieces
WHERE stop > 0
)
SELECT
pn AS Id,
SUBSTRING(@str, start, CASE WHEN stop > 0 THEN stop - start ELSE 512 END) AS Data
FROM
Pieces
) DECLARE @FilterTable TABLE (Data VARCHAR(512))
INSERT INTO @FilterTable (Data)
SELECT DISTINCT S.Data
FROM fnSplit(' ', 'word1 word2 word3') S -- Contains words
SELECT DISTINCT
T.*
FROM
MyTable T
INNER JOIN @FilterTable F1 ON T.Column1 LIKE '%' + F1.Data + '%'
LEFT JOIN @FilterTable F2 ON T.Column1 NOT LIKE '%' + F2.Data + '%'
WHERE
F2.Data IS NULLInvece di SELECT * FROM MyTable WHERE Column1 CONTAINS 'word1 word2 word3', aggiungi E tra quelle parole come:
SELECT * FROM MyTable WHERE Column1 CONTAINS 'word1 And word2 And word3'per i dettagli, consultare qui https://msdn.microsoft.com/en-us/library/ms187787.aspx
AGGIORNARE
Per selezionare le frasi, usa virgolette doppie come:
SELECT * FROM MyTable WHERE Column1 CONTAINS '"Phrase one" And word2 And "Phrase Two"'ps devi prima abilitare la ricerca full-text sulla tabella prima di usare la parola chiave contiene. per maggiori dettagli, vedere qui https://docs.microsoft.com/en-us/sql/relational-d database/ search/ get- started- with- full- text- search
SELECT * FROM MyTable WHERE
Column1 LIKE '%word1%'
AND Column1 LIKE '%word2%'
AND Column1 LIKE '%word3%'Modificato ORin ANDbase alla modifica alla domanda.
Se si utilizza Oracle Database, è possibile ottenere ciò utilizzando la query contiene . Contiene query più veloci di una query simile.
Se hai bisogno di tutte le parole
SELECT * FROM MyTable WHERE CONTAINS(Column1,'word1 and word2 and word3', 1) > 0Se hai bisogno di una qualsiasi delle parole
SELECT * FROM MyTable WHERE CONTAINS(Column1,'word1 or word2 or word3', 1) > 0Contiene l'indice di necessità di tipo CONTEXT sulla colonna.
CREATE INDEX SEARCH_IDX ON MyTable(Column) INDEXTYPE IS CTXSYS.CONTEXTSe vuoi solo trovare una corrispondenza.
SELECT * FROM MyTable WHERE INSTR('word1 word2 word3',Column1)<>0Server SQL :
CHARINDEX(Column1, 'word1 word2 word3', 1)<>0Per ottenere la corrispondenza esatta. L'esempio (';a;ab;ac;',';b;')non otterrà una corrispondenza.
SELECT * FROM MyTable WHERE INSTR(';word1;word2;word3;',';'||Column1||';')<>0prova a utilizzare la "ricerca tesarus" nell'indice full-text in MS SQL Server. È molto meglio che usare "%" nella ricerca se hai milioni di record. tesarus ha un piccolo consumo di memoria rispetto agli altri. prova a cercare queste funzioni :)
il modo migliore è fare l'indice full-text su una colonna della tabella e usare contenere anziché LIKE
SELECT * FROM MyTable WHERE
contains(Column1 , N'word1' )
AND contains(Column1 , N'word2' )
AND contains(Column1 , N'word3' )Uno dei modi più semplici per ottenere ciò che è menzionato nella domanda è usare CONTAINS con NEAR o '~'. Ad esempio, le seguenti query ci forniranno tutte le colonne che includono specificamente word1, word2 e word3.
SELECT * FROM MyTable WHERE CONTAINS(Column1, 'word1 NEAR word2 NEAR word3')
SELECT * FROM MyTable WHERE CONTAINS(Column1, 'word1 ~ word2 ~ word3')Inoltre, CONTAINSTABLE restituisce un rango per ciascun documento in base alla vicinanza di "parola1", "parola2" e "parola3". Ad esempio, se un documento contiene la frase "La parola 1 è la parola 2 e la parola 3", la sua classificazione sarebbe alta perché i termini sono più vicini tra loro che in altri documenti.
Un'altra cosa che vorrei aggiungere è che possiamo anche usare prossimità_term per trovare colonne in cui le parole si trovano all'interno di una distanza specifica tra loro all'interno della frase di colonna.
Questo dovrebbe idealmente essere fatto con l'aiuto della ricerca full text del server sql se si utilizza. Tuttavia, se non riesci a farlo funzionare sul tuo DB per qualche motivo, ecco una soluzione ad alte prestazioni: -
-- table to search in
CREATE TABLE dbo.myTable
(
myTableId int NOT NULL IDENTITY (1, 1),
code varchar(200) NOT NULL,
description varchar(200) NOT NULL -- this column contains the values we are going to search in
) ON [PRIMARY]
GO
-- function to split space separated search string into individual words
CREATE FUNCTION [dbo].[fnSplit] (@StringInput nvarchar(max),
@Delimiter nvarchar(1))
RETURNS @OutputTable TABLE (
id nvarchar(1000)
)
AS
BEGIN
DECLARE @String nvarchar(100);
WHILE LEN(@StringInput) > 0
BEGIN
SET @String = LEFT(@StringInput, ISNULL(NULLIF(CHARINDEX(@Delimiter, @StringInput) - 1, -1),
LEN(@StringInput)));
SET @StringInput = SUBSTRING(@StringInput, ISNULL(NULLIF(CHARINDEX
(
@Delimiter, @StringInput
),
0
), LEN
(
@StringInput)
)
+ 1, LEN(@StringInput));
INSERT INTO @OutputTable (id)
VALUES (@String);
END;
RETURN;
END;
GO
-- this is the search script which can be optionally converted to a stored procedure /function
declare @search varchar(max) = 'infection upper acute genito'; -- enter your search string here
-- the searched string above should give rows containing the following
-- infection in upper side with acute genitointestinal tract
-- acute infection in upper teeth
-- acute genitointestinal pain
if (len(trim(@search)) = 0) -- if search string is empty, just return records ordered alphabetically
begin
select 1 as Priority ,myTableid, code, Description from myTable order by Description
return;
end
declare @splitTable Table(
wordRank int Identity(1,1), -- individual words are assinged priority order (in order of occurence/position)
word varchar(200)
)
declare @nonWordTable Table( -- table to trim out auxiliary verbs, prepositions etc. from the search
id varchar(200)
)
insert into @nonWordTable values
('of'),
('with'),
('at'),
('in'),
('for'),
('on'),
('by'),
('like'),
('up'),
('off'),
('near'),
('is'),
('are'),
(','),
(':'),
(';')
insert into @splitTable
select id from dbo.fnSplit(@search,' '); -- this function gives you a table with rows containing all the space separated words of the search like in this e.g., the output will be -
-- id
-------------
-- infection
-- upper
-- acute
-- genito
delete s from @splitTable s join @nonWordTable n on s.word = n.id; -- trimming out non-words here
declare @countOfSearchStrings int = (select count(word) from @splitTable); -- count of space separated words for search
declare @highestPriority int = POWER(@countOfSearchStrings,3);
with plainMatches as
(
select myTableid, @highestPriority as Priority from myTable where Description like @search -- exact matches have highest priority
union
select myTableid, @highestPriority-1 as Priority from myTable where Description like @search + '%' -- then with something at the end
union
select myTableid, @highestPriority-2 as Priority from myTable where Description like '%' + @search -- then with something at the beginning
union
select myTableid, @highestPriority-3 as Priority from myTable where Description like '%' + @search + '%' -- then if the word falls somewhere in between
),
splitWordMatches as( -- give each searched word a rank based on its position in the searched string
-- and calculate its char index in the field to search
select myTable.myTableid, (@countOfSearchStrings - s.wordRank) as Priority, s.word,
wordIndex = CHARINDEX(s.word, myTable.Description) from myTable join @splitTable s on myTable.Description like '%'+ s.word + '%'
-- and not exists(select myTableid from plainMatches p where p.myTableId = myTable.myTableId) -- need not look into myTables that have already been found in plainmatches as they are highest ranked
-- this one takes a long time though, so commenting it, will have no impact on the result
),
matchingRowsWithAllWords as (
select myTableid, count(myTableid) as myTableCount from splitWordMatches group by(myTableid) having count(myTableid) = @countOfSearchStrings
)
, -- trim off the CTE here if you don't care about the ordering of words to be considered for priority
wordIndexRatings as( -- reverse the char indexes retrived above so that words occuring earlier have higher weightage
-- and then normalize them to sequential values
select s.myTableid, Priority, word, ROW_NUMBER() over (partition by s.myTableid order by wordindex desc) as comparativeWordIndex
from splitWordMatches s join matchingRowsWithAllWords m on s.myTableId = m.myTableId
)
,
wordIndexSequenceRatings as ( -- need to do this to ensure that if the same set of words from search string is found in two rows,
-- their sequence in the field value is taken into account for higher priority
select w.myTableid, w.word, (w.Priority + w.comparativeWordIndex + coalesce(sequncedPriority ,0)) as Priority
from wordIndexRatings w left join
(
select w1.myTableid, w1.priority, w1.word, w1.comparativeWordIndex, count(w1.myTableid) as sequncedPriority
from wordIndexRatings w1 join wordIndexRatings w2 on w1.myTableId = w2.myTableId and w1.Priority > w2.Priority and w1.comparativeWordIndex>w2.comparativeWordIndex
group by w1.myTableid, w1.priority,w1.word, w1.comparativeWordIndex
)
sequencedPriority on w.myTableId = sequencedPriority.myTableId and w.Priority = sequencedPriority.Priority
),
prioritizedSplitWordMatches as ( -- this calculates the cumulative priority for a field value
select w1.myTableId, sum(w1.Priority) as OverallPriority from wordIndexSequenceRatings w1 join wordIndexSequenceRatings w2 on w1.myTableId = w2.myTableId
where w1.word <> w2.word group by w1.myTableid
),
completeSet as (
select myTableid, priority from plainMatches -- get plain matches which should be highest ranked
union
select myTableid, OverallPriority as priority from prioritizedSplitWordMatches -- get ranked split word matches (which are ordered based on word rank in search string and sequence)
),
maximizedCompleteSet as( -- set the priority of a field value = maximum priority for that field value
select myTableid, max(priority) as Priority from completeSet group by myTableId
)
select priority, myTable.myTableid , code, Description from maximizedCompleteSet m join myTable on m.myTableId = myTable.myTableId
order by Priority desc, Description -- order by priority desc to get highest rated items on top
--offset 0 rows fetch next 50 rows only -- optional paging
DECLARE @SearchStr nvarchar(100)
SET @SearchStr = ' '
CREATE TABLE #Results (ColumnName nvarchar(370), ColumnValue nvarchar(3630))
SET NOCOUNT ON
DECLARE @TableName nvarchar(256), @ColumnName nvarchar(128), @SearchStr2 nvarchar(110)
SET @TableName = ''
SET @SearchStr2 = QUOTENAME('%' + @SearchStr + '%','''')
WHILE @TableName IS NOT NULL
BEGIN
SET @ColumnName = ''
SET @TableName =
(
SELECT MIN(QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME))
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE'
AND QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME) > @TableName
AND OBJECTPROPERTY(
OBJECT_ID(
QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME)
), 'IsMSShipped'
) = 0
)
WHILE (@TableName IS NOT NULL) AND (@ColumnName IS NOT NULL)
BEGIN
SET @ColumnName =
(
SELECT MIN(QUOTENAME(COLUMN_NAME))
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_SCHEMA = PARSENAME(@TableName, 2)
AND TABLE_NAME = PARSENAME(@TableName, 1)
AND DATA_TYPE IN ('char', 'varchar', 'nchar', 'nvarchar', 'int', 'decimal')
AND QUOTENAME(COLUMN_NAME) > @ColumnName
)
IF @ColumnName IS NOT NULL
BEGIN
INSERT INTO #Results
EXEC
(
'SELECT ''' + @TableName + '.' + @ColumnName + ''', LEFT(' + @ColumnName + ', 3630) FROM ' + @TableName + ' (NOLOCK) ' +
' WHERE ' + @ColumnName + ' LIKE ' + @SearchStr2
)
END
END
END
SELECT ColumnName, ColumnValue FROM #Results
DROP TABLE #Resultsselect * from table where name regexp '^word[1-3]$'o
select * from table where name in ('word1','word2','word3')