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AnswerRe: Get modified column names from CDC Pin
Mycroft Holmes17-Mar-16 12:43
professionalMycroft Holmes17-Mar-16 12:43 
GeneralRe: Get modified column names from Change Data Capture Pin
indian14317-Mar-16 12:59
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QuestionHow to design database to store userlog of changing data? Pin
hmanhha15-Mar-16 9:38
hmanhha15-Mar-16 9:38 
AnswerRe: How to design database to store userlog of changing data? Pin
Richard MacCutchan15-Mar-16 10:48
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AnswerRe: How to design database to store userlog of changing data? Pin
Mycroft Holmes15-Mar-16 14:14
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AnswerMessage Closed Pin
15-Mar-16 22:10
Luke Lonergan15-Mar-16 22:10 
GeneralRe: How to design database to store userlog of changing data? Pin
CHill6016-Mar-16 0:01
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QuestionSQLite: Correlated "EXISTS" vs uncorrelated "IN" Pin
Midi_Mick13-Mar-16 5:47
professionalMidi_Mick13-Mar-16 5:47 
Just after opinions here: which of these would be the best practice for an SQLite database:
SQL
DELETE FROM Messages WHERE Account = @acct AND NOT EXISTS (SELECT * FROM temp.IdList WHERE MailId=Id)
or
DELETE FROM Messages WHERE Account = @acct AND Id NOT IN (SELECT MailId FROM temp.IdList)

Indexes exist for both Messages(Account, Id) and temp.IdList(MailId)
Each table may hold in excess of 20000 rows

From what I understand, the correlated exists will need to be evaluated for each row of the Messages table, but will stop evaluating as soon as it finds a match (and being indexed, should be pretty quick). However, with the IN expression, the full result set is evaluated only once, but the comparison will be against that full set.

Cheers,

Mick
AnswerRe: SQLite: Correlated "EXISTS" vs uncorrelated "IN" Pin
Richard Andrew x6413-Mar-16 6:02
professionalRichard Andrew x6413-Mar-16 6:02 
AnswerRe: SQLite: Correlated "EXISTS" vs uncorrelated "IN" Pin
GuyThiebaut13-Mar-16 7:06
professionalGuyThiebaut13-Mar-16 7:06 
AnswerRe: SQLite: Correlated "EXISTS" vs uncorrelated "IN" Pin
CHill6013-Mar-16 10:12
mveCHill6013-Mar-16 10:12 
AnswerRe: SQLite: Correlated "EXISTS" vs uncorrelated "IN" Pin
Jörgen Andersson13-Mar-16 11:00
professionalJörgen Andersson13-Mar-16 11:00 
AnswerRe: SQLite: Correlated "EXISTS" vs uncorrelated "IN" Pin
Midi_Mick14-Mar-16 2:25
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QuestionUnable to write data on to the Excel Pin
indian1438-Mar-16 7:40
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AnswerRe: Unable to write data on to the Excel Pin
indian1438-Mar-16 12:34
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GeneralRe: Unable to write data on to the Excel Pin
Mycroft Holmes8-Mar-16 13:17
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GeneralRe: Unable to write data on to the Excel Pin
indian1439-Mar-16 4:19
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GeneralRe: Unable to write data on to the Excel - Resolved Pin
indian1439-Mar-16 7:19
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GeneralRe: Unable to write data on to the Excel - limitation Pin
indian1439-Mar-16 10:38
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QuestionMigrate columns which have carriage return and line feed Pin
indian1437-Mar-16 12:02
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AnswerRe: Migrate columns which have carriage return and line feed Pin
Richard MacCutchan7-Mar-16 22:04
mveRichard MacCutchan7-Mar-16 22:04 
QuestionRe: Migrate columns which have carriage return and line feed Pin
CHill608-Mar-16 2:26
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AnswerRe: Migrate columns which have carriage return and line feed Pin
indian1438-Mar-16 7:36
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QuestionHow to store procedure or function to use in asp.net Pin
hmanhha4-Mar-16 15:52
hmanhha4-Mar-16 15:52 
AnswerRe: How to store procedure or function to use in asp.net Pin
Richard MacCutchan4-Mar-16 22:22
mveRichard MacCutchan4-Mar-16 22:22 

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