Le statistiche non vengono aggiornate automaticamente fino a quando le statistiche non saranno nuovamente necessarie. alias, il TRUNCATE non lo fa. Quindi "No".
La risposta originale era "Sì" perché non è automatica come parte di TRUNCATE. Dipende da come leggi la domanda :-)
Ricorda, le statistiche vengono aggiornate automaticamente quando necessario da una query (ad esempio il numero di modifiche di riga). Da "Statistiche dell'indice " in BOL
Un modo per verificare utilizzando STATS_DATE ...
SELECT
name AS index_name,
STATS_DATE(object_id, index_id)
FROM
sys.indexes
WHERE
object_id = OBJECT_ID('MyTruncatedTable')
Modifica :Volevo essere sicuro :-)
Vedrai che le statistiche vengono aggiornate solo dalle istruzioni SELECT, non da INSERT, DELETE o TRUNCATE
IF OBJECT_ID('dbo.foo') IS NOT NULL DROP TABLE dbo.foo
CREATE TABLE dbo.foo (
bar int NOT NULL IDENTITY (1, 1) PRIMARY KEY,
thing int NOT NULL
)
CREATE INDEX IX_thing ON dbo.foo (thing)
INSERT dbo.foo (thing) SELECT c1.object_id FROM sys.columns c1, sys.columns c2
SELECT
name AS index_name,
STATS_DATE(object_id, index_id) AS AfterLoad
FROM sys.indexes WHERE object_id = OBJECT_ID('dbo.foo')
SELECT DISTINCT thing FROM dbo.foo ORDER BY thing DESC
SELECT
name AS index_name,
STATS_DATE(object_id, index_id) AS AfterFirstQuery
FROM sys.indexes WHERE object_id = OBJECT_ID('dbo.foo')
DELETE TOP (50000) dbo.foo
SELECT
name AS index_name,
STATS_DATE(object_id, index_id) AS AfterDelete
FROM sys.indexes WHERE object_id = OBJECT_ID('dbo.foo')
SELECT DISTINCT thing FROM dbo.foo ORDER BY thing DESC
SELECT
name AS index_name,
STATS_DATE(object_id, index_id) AS After2ndQuery
FROM sys.indexes WHERE object_id = OBJECT_ID('dbo.foo')
TRUNCATE TABLE dbo.foo
SELECT
name AS index_name,
STATS_DATE(object_id, index_id) AS AfterTruncate
FROM sys.indexes WHERE object_id = OBJECT_ID('dbo.foo')
SELECT DISTINCT thing FROM dbo.foo ORDER BY thing DESC
SELECT
name AS index_name,
STATS_DATE(object_id, index_id) AS After3rdQuery
FROM sys.indexes WHERE object_id = OBJECT_ID('dbo.foo')
