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diff --git a/www/conflict.html b/www/conflict.html new file mode 100644 index 0000000..4fd6e17 --- /dev/null +++ b/www/conflict.html @@ -0,0 +1,179 @@ +<!DOCTYPE html> +<html><head> +<meta name="viewport" content="width=device-width, initial-scale=1.0"> +<meta http-equiv="content-type" content="text/html; charset=UTF-8"> +<link href="sqlite.css" rel="stylesheet"> +<title>Constraint Conflict Resolution in SQLite</title> +<!-- path= --> +</head> +<body> +<div class=nosearch> +<a href="index.html"> +<img class="logo" src="images/sqlite370_banner.gif" alt="SQLite" border="0"> +</a> +<div><!-- IE hack to prevent disappearing logo --></div> +<div class="tagline desktoponly"> +Small. Fast. 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If no transaction is +active (other than the implied transaction that is created on every +command) then this algorithm works the same as ABORT.</p></dd> + +<dt><b>ABORT</b></dt> +<dd><p>When a constraint violation occurs, the command backs out +any prior changes it might have made and aborts with a return code +of SQLITE_CONSTRAINT. But no ROLLBACK is executed so changes +from prior commands within the same transaction +are preserved. This is the default behavior for SQLite.</p></dd> + +<dt><b>FAIL</b></dt> +<dd><p>When a constraint violation occurs, the command aborts with a +return code SQLITE_CONSTRAINT. But any changes to the database that +the command made prior to encountering the constraint violation +are preserved and are not backed out. For example, if an UPDATE +statement encountered a constraint violation on the 100th row that +it attempts to update, then the first 99 row changes are preserved +but change to rows 100 and beyond never occur.</p></dd> + +<dt><b>IGNORE</b></dt> +<dd><p>When a constraint violation occurs, the one row that contains +the constraint violation is not inserted or changed. But the command +continues executing normally. Other rows before and after the row that +contained the constraint violation continue to be inserted or updated +normally. No error is returned.</p></dd> + +<dt><b>REPLACE</b></dt> +<dd><p>When a UNIQUE constraint violation occurs, the pre-existing row +that caused the constraint violation is removed prior to inserting +or updating the current row. Thus the insert or update always occurs. +The command continues executing normally. No error is returned.</p></dd> +</dl> +<p align="center"><small><i>This page last modified on <a href="https://sqlite.org/docsrc/honeypot" id="mtimelink" data-href="https://sqlite.org/docsrc/finfo/pages/conflict.in?m=1ad44025d4f9e5f52">2014-08-15 14:59:54</a> UTC </small></i></p> + |