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--- |
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title: "sqlFunctions-Doc" |
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output: html_document |
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--- |
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```{r setup, include=FALSE} |
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knitr::opts_chunk$set(echo = TRUE) |
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``` |
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## sqlDropLast |
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### Description |
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Removes from Database the last (or the amount specified) entry. |
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### Usage |
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sqlDropLast(conn, tablename, droplast=1) |
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### Arguments |
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Argument|Description |
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---|--- |
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conn|connection handle returned by odbcConnect. |
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tablename|character: a database table name accessible from the connected DSN. |
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droplast|the amount of lines to be removed from the table strating from tail. By default, it removes only 1 line. |
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### Details |
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Removes from Database the last (or the amount specified) entry. |
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### Value |
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Invisibly for success (and failures cause errors). |
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### Examples |
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```r |
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dta<-odbcConnect("test") |
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sqlDropLast(dta, "TableTest") |
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``` |
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### Function |
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```r |
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sqlDropLast<-function(conn, tablename, droplast=1){ |
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table<-sqlFetch(conn, tablename) |
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table<-table[1:(nrow(table)-droplast),] |
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sqlSave(conn, table, tablename = tablename, safer = F) |
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} |
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``` |