Dapper is a single file you can drop in to your project that will extend your IDbConnection interface. [...]

A key feature of Dapper is performance. The following metrics show how long it takes to execute 500 SELECT statements against a DB and map the data returned to objects.

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In my code ramblings during the developement of Code Zauker, I ended up studing a bit NoSql  database.

Code zauker started using Redis, because Redis is a very bold memory-based no-sql db. Redis also support complex data type like sorted set, lists and so on, which was very userful. Anyway I needed a very fast way of doing statistics on data collected by code zauker, for inspecting data and finding out new feature I’d like to add to it. Worst, my current pocket pose a hard limit on a redis instance in terms of available RAM. So I started thinking a lot about a redis drop-in replacement for Code Zauker.

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E’ facile fare un backup con sql server: Basta selezionare tasto destro Tasks>>Backup su un db. Ma come fare il restore?… Ecco un semplice script che chiarisce la cosa (non sempre lampante dallo wizard di restore….): [sql] – Usare il seguente comando per recuperare i parametri sorgente da usare nella MOVE – Nel nostro caso ssaranno MY_BACKUP e MY_BACKUP_log RESTORE FILELISTONLY FROM DISK = N’C:\TEMP\MY_BACKUP\Backup.bak’ ;

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 Come evitare iniezione SQL: lato SQL Server (SP_EXECUTESQL)

In generale va evitato nel modo più assoluto la scrittura di query sql diamiche.

Va evitato cioè  l’uso lato SQL Server di sp_executesql e EXEC

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I stumbled upon a very brain-f**k error on Oracle 10g on these days.

Context: the following query [sql]SELECT * FROM (
SELECT TO_NUMBER(CUSTOMER_ID) AS SNDG FROM BAD_CODES_TABLE WHERE
AND I_LIKE=UPPER(‘STATIC_CONDITION’) AND CUSTOMER_ID NOT LIKE ‘%P%’ ) S WHERE TO_NUMBER(S.SNDG) >2000[/sql] could trigger a Invalid number if CUSTOMER_ID column contains invalid numbers.

Why?

Well…if you ask to “explain plan”, you will get something like

• a table full scan
  • Filter Predicates AND
    • I_LIKE=UPPER('STATIC_CONDITION')
    • TO_NUMBER(S.SNDG) >2000
    • CUSTOMER_ID NOT LIKE '%P%'

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Oracle SQL Developer is full of nice feature, damned by a overwhelming options pane, like the one I will describe to you right now.

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Oracle SQL Developer is full of nice feature, damned by a overwhelming options pane, like the one I will describe to you right now.

Even if  Oracle databases (<12) does not support auto increment, you can easily ask to your sql data modeler to generate for you a sequence and a trigger in a automatic way.

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On some environment, on some customers, Oracle connections are drop after some idle time (i.e. 2 minutes).

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In Italian language we have accent words like àèéìòù

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Sometimes you need to remove nasty duplicate on a table, based on a subset of the column. On every big database there is something called “rowid” which can be used to indentify a column in a unique way. On PostgreSQL is called ctid, as we shall see:

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