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Editorial Team
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Asked: 2026-06-12T01:42:16+00:00

I often verify logs in SQLServer and my query usually looks like this (where

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I often verify logs in SQLServer and my query usually looks like this (where Type = 0 means error):

SELECT * 
FROM Logs 
WHERE Type = 0 
ORDER BY Timestamp

But most of the time, I’m not only interested by the error itself but also at what happened immediately before the error.

Is it possible, with SQLServer, to query n lines above/under (relative to the primary key) each line matching the WHERE clause of the query?

Ex. With my query I would only get lines 125 & 130. I would like [123, 124, 125] and [128, 129, 130].

PrimaryKey  Timestamp             Type  Description
123         2012-09-17 03:41:46.240 1   Working.
124         2012-09-17 03:42:46.240 1   Database backup.
125         2012-09-17 03:43:46.240 0   Access violation.
126         2012-09-17 03:44:46.240 1   Working.
127         2012-09-17 03:45:46.240 1   Working.
128         2012-09-17 03:46:46.240 1   Working.
129         2012-09-17 03:47:46.240 1   Backup.
130         2012-09-17 03:48:46.240 0   Corrupted.
131         2012-09-17 03:49:46.240 1   Working.

Thank you.

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1 Answer

  1. Editorial Team

    I would do it as follows:

    SELECT 
    L2.* 
FROM 
    Logs L1
    JOIN Logs L2
    ON 
        L1.PrimaryKey = L2.PrimaryKey OR 
        L1.PrimaryKey = L2.PrimaryKey - 1 OR
        L1.PrimaryKey = L2.PrimaryKey + 1
WHERE
    L1.Type = 0

    The results would be as follows:

    PrimaryKey  TS                      Type        Description
----------- ----------------------- ----------- -----------------
124         2012-09-17 03:42:46.240 1           Database backup.
125         2012-09-17 03:43:46.240 0           Access violation.
126         2012-09-17 03:44:46.240 1           Working.
129         2012-09-17 03:47:46.240 1           Backup.
130         2012-09-17 03:48:46.240 0           Corrupted.
131         2012-09-17 03:49:46.240 1           Working.

    You can modify the join conditions using the relational operators to retrieve n lines above and below the matching line.

    If the PrimaryKey column is not guaranteed to be sequential, then assuming that the records are always ordered by Timestamp in ASC order, the following query will fetch the before and after records to a selected one:

    WITH LogsTable (PrimaryKey, TS, Type, Description, Rank) AS
(
    SELECT 
        PrimaryKey, 
        TS, 
        Type, 
        Description, 
        ROW_NUMBER() OVER (ORDER BY TS ASC) as 'Rank' 
    FROM 
        Logs
)
SELECT 
    L2.* 
FROM 
    LogsTable L1
    JOIN LogsTable L2
    ON 
        L1.Rank = L2.Rank OR 
        L1.Rank = L2.Rank - 1 OR
        L1.Rank = L2.Rank + 1
WHERE
    L1.Type = 0
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