New function SCOPE_IDENTITY().

h2/src/docsrc/help/help.csv

@@ -44,12 +44,13 @@ INSERT INTO TEST VALUES(1, 'Hello')
 "
 
 "Commands (DML)","UPDATE","
-UPDATE tableName SET { columnName= { DEFAULT | expression } } [,...]
+UPDATE tableName [ [ AS ] newTableAlias ] SET { columnName= { DEFAULT | expression } } [,...]
 [ WHERE expression ]
 ","
 Updates data in a table.
 ","
-UPDATE TEST SET NAME='Hi' WHERE ID=1
+UPDATE TEST SET NAME='Hi' WHERE ID=1;
+UPDATE PERSON P SET NAME=(SELECT A.NAME FROM ADDRESS A WHERE A.ID=P.ID);
 "
 
 "Commands (DML)","DELETE","
@@ -1034,7 +1035,7 @@ SET IGNORECASE TRUE
 SET LOCK_MODE int
 ","
 Sets the lock mode. The values 0, 1, 2, and 3 are supported. The default is 3
-(READ_COMMITTED).
+(READ_COMMITTED). This setting affects all connections.
 
 The value 0 means no locking (should only be used for testing; also known as
 READ_UNCOMMITTED). Please note that using SET LOCK_MODE 0 while at the same time
@@ -3229,6 +3230,8 @@ CALL GREATEST(1, 2, 3);
 IDENTITY()
 ","
 Returns the last inserted identity value for this session.
+This value changes whenever a new sequence number was generated,
+even within a trigger or Java function. See also SCOPE_IDENTITY().
 This method returns a long.
 ","
 CALL IDENTITY();
@@ -3351,6 +3354,16 @@ Returns the name of the default  schema for this session.
 CALL SCHEMA()
 "
 
+"Functions (System)","SCOPE_IDENTITY","
+SCOPE_IDENTITY()
+","
+Returns the last inserted identity value for this session for the current scope.
+Changes within triggers and Java functions are ignored. See also IDENTITY().
+This method returns a long.
+","
+CALL SCOPE_IDENTITY();
+"
+
 "Functions (System)","SESSION_ID","
 SESSION_ID()
 ","

h2/src/main/org/h2/engine/Database.java

@@ -1993,6 +1993,10 @@ public class Database implements DataHandler {
     public void setLockMode(int lockMode) throws SQLException {
         switch (lockMode) {
         case Constants.LOCK_MODE_OFF:
+            if (multiThreaded) {
+                // currently the combination of LOCK_MODE=0 and MULTI_THREADED is not supported
+                throw Message.getSQLException(ErrorCode.CANNOT_CHANGE_SETTING_WHEN_OPEN_1, "LOCK_MODE=0 & MULTI_THREADED");
+            }
         case Constants.LOCK_MODE_READ_COMMITTED:
         case Constants.LOCK_MODE_TABLE:
         case Constants.LOCK_MODE_TABLE_GC:

h2/src/main/org/h2/engine/FunctionAlias.java

@@ -292,6 +292,7 @@ public class FunctionAlias extends DbObjectBase {
                 }
             }
             boolean old = session.getAutoCommit();
+            Value identity = session.getScopeIdentity();
             try {
                 session.setAutoCommit(false);
                 try {
@@ -306,6 +307,7 @@ public class FunctionAlias extends DbObjectBase {
                     throw Message.convert(e);
                 }
             } finally {
+                session.setScopeIdentity(identity);
                 session.setAutoCommit(old);
             }
         }

h2/src/main/org/h2/engine/Session.java

@@ -67,6 +67,7 @@ public class Session extends SessionWithState {
     private LogSystem logSystem;
     private int lockTimeout;
     private Value lastIdentity = ValueLong.get(0);
+    private Value scopeIdentity = ValueLong.get(0);
     private int firstUncommittedLog = LogSystem.LOG_WRITTEN;
     private int firstUncommittedPos = LogSystem.LOG_WRITTEN;
     private HashMap<String, Integer> savepoints;
@@ -686,6 +687,7 @@ public class Session extends SessionWithState {
     }
 
     public void setLastIdentity(Value last) {
+        this.scopeIdentity = last;
         this.lastIdentity = last;
     }
 
@@ -1161,4 +1163,12 @@ public class Session extends SessionWithState {
         return objectId++;
     }
 
+    public void setScopeIdentity(Value scopeIdentity) {
+        this.scopeIdentity = scopeIdentity;
+    }
+
+    public Value getScopeIdentity() {
+        return scopeIdentity;
+    }
+
 }

h2/src/main/org/h2/expression/Function.java

@@ -91,8 +91,8 @@ public class Function extends Expression implements FunctionCall {
             CURRENT_TIMESTAMP = 119, EXTRACT = 120, FORMATDATETIME = 121, PARSEDATETIME = 122,
             ISO_YEAR = 123, ISO_WEEK = 124, ISO_DAY_OF_WEEK = 125;
 
-    public static final int DATABASE = 150, USER = 151, CURRENT_USER = 152, IDENTITY = 153, AUTOCOMMIT = 154,
-            READONLY = 155, DATABASE_PATH = 156, LOCK_TIMEOUT = 157;
+    public static final int DATABASE = 150, USER = 151, CURRENT_USER = 152, IDENTITY = 153, SCOPE_IDENTITY = 154,
+            AUTOCOMMIT = 155, READONLY = 156, DATABASE_PATH = 157, LOCK_TIMEOUT = 158;
 
     public static final int IFNULL = 200, CASEWHEN = 201, CONVERT = 202, CAST = 203, COALESCE = 204, NULLIF = 205,
             CASE = 206, NEXTVAL = 207, CURRVAL = 208, ARRAY_GET = 209, CSVREAD = 210, CSVWRITE = 211,
@@ -286,6 +286,7 @@ public class Function extends Expression implements FunctionCall {
         addFunctionNotDeterministic("USER", USER, 0, Value.STRING);
         addFunctionNotDeterministic("CURRENT_USER", CURRENT_USER, 0, Value.STRING);
         addFunctionNotDeterministic("IDENTITY", IDENTITY, 0, Value.LONG);
+        addFunctionNotDeterministic("SCOPE_IDENTITY", SCOPE_IDENTITY, 0, Value.LONG);
         addFunctionNotDeterministic("IDENTITY_VAL_LOCAL", IDENTITY, 0, Value.LONG);
         addFunctionNotDeterministic("LAST_INSERT_ID", IDENTITY, 0, Value.LONG);
         addFunctionNotDeterministic("LASTVAL", IDENTITY, 0, Value.LONG);
@@ -688,6 +689,9 @@ public class Function extends Expression implements FunctionCall {
         case IDENTITY:
             result = session.getLastIdentity();
             break;
+        case SCOPE_IDENTITY:
+            result = session.getScopeIdentity();
+            break;
         case AUTOCOMMIT:
             result = ValueBoolean.get(session.getAutoCommit());
             break;