transactions

问题 I'm pretty new to transactions. Before, what I was doing was something like: Code Block 1 $db = new PDO(...); $stmt = $db->prepare(...); if($stmt->execute()){ // success return true; }else{ // failed return false; } But in an attempt to group multiple queries into a single transaction, I'm now using something like: Code Block 2 $db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); $db->beginTransaction(); try{ $stmt = $db->prepare(... 1 ...); $stmt->execute(); $stmt = $db->prepare(...

问题 I'm pretty new to transactions. Before, what I was doing was something like: Code Block 1 $db = new PDO(...); $stmt = $db->prepare(...); if($stmt->execute()){ // success return true; }else{ // failed return false; } But in an attempt to group multiple queries into a single transaction, I'm now using something like: Code Block 2 $db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); $db->beginTransaction(); try{ $stmt = $db->prepare(... 1 ...); $stmt->execute(); $stmt = $db->prepare(...

问题 More transaction questions! What I have right now is a mess of strung-together queries, that are all manually reversed if any fail: Code Block 1 $stmt1 = $db->prepare(...); // Update table1, set col=col+1 if($stmt1 = $db->execute(...)){ $stmt2 = $db->prepare(...); // Insert into table2, id=12345 if($stmt2 = $db->execute(...)){ $stmt3 = $db->prepare(...); // Select val from table3 if($stmt3 = $db->execute(...)){ $result = $stmt3->fetchAll(); if($result[0]['val'] == something){ $stmt4 = $db-

问题 So I have values I need to update in my datastore. I am using a transaction do so as seen below. After the update has been committed I send a result back to the client letting them know the update has went through. The client then sends another request for an updated list of items. All code executes correctly as far as I can tell, no errors thrown and eventually I do get the update requested showing as expected. My issue is even after the commit sometimes it is several seconds sometimes

问题 So I have values I need to update in my datastore. I am using a transaction do so as seen below. After the update has been committed I send a result back to the client letting them know the update has went through. The client then sends another request for an updated list of items. All code executes correctly as far as I can tell, no errors thrown and eventually I do get the update requested showing as expected. My issue is even after the commit sometimes it is several seconds sometimes

问题 I have a table with bills. Every bill has an id that comes from the DB after I insert a new record. The field is an INTEGER with AUTO_INCREMENT set. If I insert a new record as part of a transaction and I have to rollback this transaction, the ID is taken and gone. So the next record becomes the ID one higher, even though this ID is not in use. It would be better for the bills to have a linear numbering, so the accounting can figure out if something is wrong. 回答1: For concurrency reasons, the

问题 I am looking at the Activty Monitor for SQL Server 2005 and we have some processes that are taking up large amounts of the CPU. When I look at what is trying to be run I get: set transaction isolation level read committed This code is not coming from any of our applications. What is causing it? What should be done? 回答1: Look at sys.dm_exec_sessions and sys.dm_exec_connections for the session ids that take up CPU. You'll find the application name, host name and process id of the client. 回答2:

问题 Since I have a "DB util" class with a DataSet QueryDB(string spName, DBInputParams inputParams) method which I use for all my calls to the database, I would like to reuse this method in order to support transacted calls. So, at the end I will have a SqlDataAdapter.Fill within a SqlTransaction. Will this be a bad practice? Because rarely I see usage of DataAdapter.Fill within a transaction and more often ExecuteReader(). Is there any catch? Edit1: The thing is that inside my transaction is

问题 After migrating to Java 8 and WildFly 8.2.0 I get this error on every Transaction UserTransaction: javax.naming.NameNotFoundException: UserTransaction [Root exception is java.lang.IllegalStateException: JBAS014237: Only session and message-driven beans with bean-managed transaction demarcation are allowed to access UserTransaction] at org.jboss.as.naming.ServiceBasedNamingStore.lookup(ServiceBasedNamingStore.java:140) at org.jboss.as.naming.ServiceBasedNamingStore.lookup

问题 Using Spring MVC, assume I have implemented a controller that handles a POST request, performs a database operation inside a transaction, and returns a result in the response body. Here is the controller and service layer: @RestController @RequiredArgsConstructor public class SomeController { private final SomeService someService; @PostMapping("/something") public SomeResult postSomething(Something something) { return someService.handle(something); } } @Service @RequiredArgsConstructor public