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提交 25b98d52 authored 作者: Evgenij Ryazanov's avatar Evgenij Ryazanov
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Allow multiple WHEN conditions in MERGE USING

上级 7e39f8a2
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正在显示 包含 274 行增加 和 196 行删除
h2/src/docsrc/help/help.csv
浏览文件 @ 25b98d52
......@@ -137,24 +137,21 @@ MERGE INTO TEST KEY(ID) VALUES(2, 'World')
MERGE INTO targetTableName [ [AS] targetAlias]
USING { ( select ) | sourceTableName }[ [AS] sourceAlias ]
ON expression
[ WHEN MATCHED THEN
[ UPDATE SET setClauseList ] [ DELETE deleteSearchCondition ] ]
[ WHEN NOT MATCHED THEN INSERT insertColumnsAndSource ]
","
Updates or deletes existing rows, and insert rows that don't exist. The ON clause
specifies the matching column expression and must be specified. If more than one row
is updated per input row, an exception is thrown.
If the source data contains duplicate rows (specifically those columns used in the
row matching ON clause), then an exception is thrown to prevent two updates applying
to the same target row.
WHEN MATCHED THEN or WHEN NOT MATCHED THEN clauses or both of them in any order should be specified.
If WHEN MATCHED THEN is specified it should contain UPDATE or DELETE clauses of both of them.
mergeWhenClause [,...]
","
Updates or deletes existing rows, and insert rows that don't exist.
The ON clause specifies the matching column expression.
Different rows from a source table may not match with the same target row,
but one source row may be matched with multiple target rows.
If statement doesn't need a source table a DUAL table can be substituted.
","
MERGE INTO TARGET_TABLE AS T USING SOURCE_TABLE AS S
ON T.ID = S.ID
WHEN MATCHED THEN
UPDATE SET T.COL1 = S.COL1 WHERE T.COL2<>'FINAL'
WHEN MATCHED THEN
DELETE WHERE T.COL2='FINAL'
WHEN NOT MATCHED THEN
INSERT (ID,COL1,COL2) VALUES(S.ID,S.COL1,S.COL2)
......@@ -162,6 +159,7 @@ MERGE INTO TARGET_TABLE AS T USING (SELECT * FROM SOURCE_TABLE) AS S
ON T.ID = S.ID
WHEN MATCHED THEN
UPDATE SET T.COL1 = S.COL1 WHERE T.COL2<>'FINAL'
WHEN MATCHED THEN
DELETE WHERE T.COL2='FINAL'
WHEN NOT MATCHED THEN
INSERT (ID,COL1,COL2) VALUES(S.ID,S.COL1,S.COL2)
......@@ -2373,6 +2371,38 @@ Long numbers are between -9223372036854775808 and 9223372036854775807.
100000
"
"Other Grammar","Merge when clause","
mergeWhenMatchedClause|mergeWhenNotMatchedClause
","
WHEN MATCHED or WHEN NOT MATCHED clause for MERGE USING command.
","
WHEN MATCHED THEN DELETE
"
"Other Grammar","Merge when matched clause","
WHEN MATCHED THEN
[ UPDATE SET setClauseList ]
[ DELETE deleteSearchCondition ]
","
WHEN MATCHED clause for MERGE USING command.
UPDATE, DELETE, or both should be specified.
If both UPDATE and DELETE are specified, DELETE can delete only rows that were updated,
WHERE condition can be used to specify which updated rows should be deleted.
This condition checks values in updated row.
","
WHEN MATCHED THEN UPDATE SET VALUE = S.VALUE
WHEN MATCHED THEN DELETE
"
"Other Grammar","Merge when not matched clause","
WHEN NOT MATCHED THEN INSERT insertColumnsAndSource
","
WHEN NOT MATCHED clause for MERGE USING command.
","
WHEN NOT MATCHED THEN INSERT (ID, NAME) VALUES (S.ID, S.NAME)
"
"Other Grammar","Name","
{ { A-Z|_ } [ { A-Z|_|0-9 } [...] ] } | quotedName
","
......
h2/src/main/org/h2/command/Parser.java
浏览文件 @ 25b98d52
......@@ -1496,20 +1496,14 @@ public class Parser {
command.setOnCondition(condition);
read("WHEN");
boolean matched = readIf("MATCHED");
if (matched) {
parseWhenMatched(command);
} else {
parseWhenNotMatched(command);
}
if (readIf("WHEN")) {
do {
boolean matched = readIf("MATCHED");
if (matched) {
parseWhenNotMatched(command);
} else {
read("MATCHED");
parseWhenMatched(command);
} else {
parseWhenNotMatched(command);
}
}
} while (readIf("WHEN"));
setSQL(command, "MERGE", start);
return command;
......@@ -1518,25 +1512,27 @@ public class Parser {
private void parseWhenMatched(MergeUsing command) {
read("THEN");
int startMatched = lastParseIndex;
boolean ok = false;
Update updateCommand = null;
if (readIf("UPDATE")) {
Update updateCommand = new Update(session);
updateCommand = new Update(session);
TableFilter filter = command.getTargetTableFilter();
updateCommand.setTableFilter(filter);
parseUpdateSetClause(updateCommand, filter, startMatched);
command.setUpdateCommand(updateCommand);
ok = true;
}
startMatched = lastParseIndex;
Delete deleteCommand = null;
if (readIf("DELETE")) {
Delete deleteCommand = new Delete(session);
deleteCommand = new Delete(session);
TableFilter filter = command.getTargetTableFilter();
deleteCommand.setTableFilter(filter);
parseDeleteGivenTable(deleteCommand, null, startMatched);
command.setDeleteCommand(deleteCommand);
ok = true;
}
if (!ok) {
if (updateCommand != null || deleteCommand != null) {
MergeUsing.WhenMatched when = new MergeUsing.WhenMatched(command);
when.setUpdateCommand(updateCommand);
when.setDeleteCommand(deleteCommand);
command.addWhen(when);
} else {
throw getSyntaxError();
}
}
......@@ -1549,7 +1545,9 @@ public class Parser {
Insert insertCommand = new Insert(session);
insertCommand.setTable(command.getTargetTable());
parseInsertGivenTable(insertCommand, command.getTargetTable());
command.setInsertCommand(insertCommand);
MergeUsing.WhenNotMatched when = new MergeUsing.WhenNotMatched(command);
when.setInsertCommand(insertCommand);
command.addWhen(when);
} else {
throw getSyntaxError();
}
......
h2/src/main/org/h2/command/dml/MergeUsing.java
浏览文件 @ 25b98d52
......@@ -15,6 +15,7 @@ import org.h2.command.CommandInterface;
import org.h2.command.Prepared;
import org.h2.engine.Right;
import org.h2.engine.Session;
import org.h2.engine.User;
import org.h2.expression.ConditionAndOr;
import org.h2.expression.Expression;
import org.h2.expression.ExpressionColumn;
......@@ -33,88 +34,191 @@ import org.h2.value.Value;
* This class represents the statement syntax
* MERGE INTO table alias USING...
*
* It does not replace the existing MERGE INTO... KEYS... form.
*
* It supports the SQL 2003/2008 standard MERGE statement:
* http://en.wikipedia.org/wiki/Merge_%28SQL%29
*
* Database management systems Oracle Database, DB2, Teradata, EXASOL, Firebird, CUBRID, HSQLDB,
* MS SQL, Vectorwise and Apache Derby & Postgres support the standard syntax of the
* SQL 2003/2008 MERGE command:
*
* MERGE INTO targetTable AS T USING sourceTable AS S ON (T.ID = S.ID)
* WHEN MATCHED THEN
* UPDATE SET column1 = value1 [, column2 = value2 ...] WHERE column1=valueUpdate
* DELETE WHERE column1=valueDelete
* WHEN NOT MATCHED THEN
* INSERT (column1 [, column2 ...]) VALUES (value1 [, value2 ...]);
*
* Only Oracle support the additional optional DELETE clause.
*
* Implementation notes:
*
* 1) The ON clause must specify 1 or more columns from the TARGET table because they are
* used in the plan SQL WHERE statement. Otherwise an exception is raised.
*
* 2) The ON clause must specify 1 or more columns from the SOURCE table/query because they
* are used to track the join key values for every source table row - to prevent any
* TARGET rows from being updated twice per MERGE USING statement.
*
* This is to implement a requirement from the MERGE INTO specification
* requiring each row from being updated more than once per MERGE USING statement.
* The source columns are used to gather the effective "key" values which have been
* updated, in order to implement this requirement.
* If the no SOURCE table/query columns are found in the ON clause, then an exception is
* raised.
*
* The update row counts of the embedded UPDATE and DELETE statements are also tracked to
* ensure no more than 1 row is ever updated. (Note One special case of this is that
* the DELETE is allowed to affect the same row which was updated by UPDATE - this is an
* Oracle only extension.)
*
* 3) UPDATE and DELETE statements are allowed to specify extra conditional criteria
* (in the WHERE clause) to allow fine-grained control of actions when a record is found.
* The ON clause conditions are always prepended to the WHERE clause of these embedded
* statements, so they will never update more than the ON join condition.
*
* 4) Previously if neither UPDATE or DELETE clause is supplied, but INSERT is supplied - the INSERT
* action is always triggered. This is because the embedded UPDATE and DELETE statement's
* returned update row count is used to detect a matching join.
* If neither of the two the statements are provided, no matching join is NEVER detected.
*
* A fix for this is now implemented as described below:
* We now generate a "matchSelect" query and use that to always detect
* a match join - rather than relying on UPDATE or DELETE statements.
*
* This is an improvement, especially in the case that if either of the
* UPDATE or DELETE statements had their own fine-grained WHERE conditions, making
* them completely different conditions than the plain ON condition clause which
* the SQL author would be specifying/expecting.
*
* An additional benefit of this solution is that this "matchSelect" query
* is used to return the ROWID of the found (or inserted) query - for more accurate
* enforcing of the only-update-each-target-row-once rule.
* It does not replace the MERGE INTO... KEYS... form.
*/
public class MergeUsing extends Prepared {
public static abstract class When {
final MergeUsing mergeUsing;
When(MergeUsing mergeUsing) {
this.mergeUsing = mergeUsing;
}
void reset() {
// Nothing to do
}
abstract int merge();
abstract void prepare();
abstract int evaluateTriggerMasks();
abstract void checkRights();
}
public static final class WhenMatched extends When {
private Update updateCommand;
private Delete deleteCommand;
private final HashSet<Long> updatedKeys = new HashSet<>();
public WhenMatched(MergeUsing mergeUsing) {
super(mergeUsing);
}
public Prepared getUpdateCommand() {
return updateCommand;
}
public void setUpdateCommand(Update updateCommand) {
this.updateCommand = updateCommand;
}
public Prepared getDeleteCommand() {
return deleteCommand;
}
public void setDeleteCommand(Delete deleteCommand) {
this.deleteCommand = deleteCommand;
}
@Override
void reset() {
updatedKeys.clear();
}
@Override
int merge() {
int countUpdatedRows = 0;
if (updateCommand != null) {
countUpdatedRows += updateCommand.update();
}
// under oracle rules these updates & delete combinations are
// allowed together
if (deleteCommand != null) {
countUpdatedRows += deleteCommand.update();
updatedKeys.clear();
}
return countUpdatedRows;
}
@Override
void prepare() {
if (updateCommand != null) {
updateCommand.setSourceTableFilter(mergeUsing.sourceTableFilter);
updateCommand.setCondition(appendOnCondition(updateCommand));
updateCommand.prepare();
}
if (deleteCommand != null) {
deleteCommand.setSourceTableFilter(mergeUsing.sourceTableFilter);
deleteCommand.setCondition(appendOnCondition(deleteCommand));
deleteCommand.prepare();
if (updateCommand != null) {
updateCommand.setUpdatedKeysCollector(updatedKeys);
deleteCommand.setKeysFilter(updatedKeys);
}
}
}
@Override
int evaluateTriggerMasks() {
int masks = 0;
if (updateCommand != null) {
masks |= Trigger.UPDATE;
}
if (deleteCommand != null) {
masks |= Trigger.DELETE;
}
return masks;
}
@Override
void checkRights() {
User user = mergeUsing.getSession().getUser();
if (updateCommand != null) {
user.checkRight(mergeUsing.targetTable, Right.UPDATE);
}
if (deleteCommand != null) {
user.checkRight(mergeUsing.targetTable, Right.DELETE);
}
}
private Expression appendOnCondition(Update updateCommand) {
if (updateCommand.getCondition() == null) {
return mergeUsing.onCondition;
}
return new ConditionAndOr(ConditionAndOr.AND, updateCommand.getCondition(), mergeUsing.onCondition);
}
private Expression appendOnCondition(Delete deleteCommand) {
if (deleteCommand.getCondition() == null) {
return mergeUsing.onCondition;
}
return new ConditionAndOr(ConditionAndOr.AND, deleteCommand.getCondition(), mergeUsing.onCondition);
}
}
public static final class WhenNotMatched extends When {
private Insert insertCommand;
public WhenNotMatched(MergeUsing mergeUsing) {
super(mergeUsing);
}
public Insert getInsertCommand() {
return insertCommand;
}
public void setInsertCommand(Insert insertCommand) {
this.insertCommand = insertCommand;
}
@Override
int merge() {
return insertCommand.update();
}
@Override
void prepare() {
insertCommand.setSourceTableFilter(mergeUsing.sourceTableFilter);
insertCommand.prepare();
}
@Override
int evaluateTriggerMasks() {
return Trigger.INSERT;
}
@Override
void checkRights() {
mergeUsing.getSession().getUser().checkRight(mergeUsing.targetTable, Right.INSERT);
}
}
// Merge fields
private Table targetTable;
Table targetTable;
private TableFilter targetTableFilter;
private Column[] columns;
private final ArrayList<Expression[]> valuesExpressionList = Utils.newSmallArrayList();
private Query query;
// MergeUsing fields
private TableFilter sourceTableFilter;
private Expression onCondition;
private Update updateCommand;
private Delete deleteCommand;
private Insert insertCommand;
TableFilter sourceTableFilter;
Expression onCondition;
private ArrayList<When> when = Utils.newSmallArrayList();
private String queryAlias;
private int countUpdatedRows;
private Select targetMatchQuery;
private final HashMap<Value, Integer> targetRowidsRemembered = new HashMap<>();
private final HashSet<Long> updatedKeys = new HashSet<>();
private int sourceQueryRowNumber;
......@@ -144,8 +248,9 @@ public class MergeUsing extends Prepared {
sourceQueryRowNumber = 0;
checkRights();
setCurrentRowNumber(0);
// Just to be sure
updatedKeys.clear();
for (When w : when) {
w.reset();
}
// process source select query data for row creation
ResultInterface rows = query.query(0);
targetTable.fire(session, evaluateTriggerMasks(), true);
......@@ -165,33 +270,19 @@ public class MergeUsing extends Prepared {
private int evaluateTriggerMasks() {
int masks = 0;
if (insertCommand != null) {
masks |= Trigger.INSERT;
}
if (updateCommand != null) {
masks |= Trigger.UPDATE;
}
if (deleteCommand != null) {
masks |= Trigger.DELETE;
for (When w : when) {
masks |= w.evaluateTriggerMasks();
}
return masks;
}
private void checkRights() {
if (insertCommand != null) {
session.getUser().checkRight(targetTable, Right.INSERT);
}
if (updateCommand != null) {
session.getUser().checkRight(targetTable, Right.UPDATE);
for (When w : when) {
w.checkRights();
}
if (deleteCommand != null) {
session.getUser().checkRight(targetTable, Right.DELETE);
}
// check the underlying tables
session.getUser().checkRight(targetTable, Right.SELECT);
session.getUser().checkRight(sourceTableFilter.getTable(),
Right.SELECT);
session.getUser().checkRight(sourceTableFilter.getTable(), Right.SELECT);
}
/**
......@@ -202,19 +293,10 @@ public class MergeUsing extends Prepared {
protected void merge(Row sourceRow) {
// put the column values into the table filter
sourceTableFilter.set(sourceRow);
if (isTargetRowFound()) {
if (updateCommand != null) {
countUpdatedRows += updateCommand.update();
}
// under oracle rules these updates & delete combinations are
// allowed together
if (deleteCommand != null) {
countUpdatedRows += deleteCommand.update();
updatedKeys.clear();
}
} else {
if (insertCommand != null) {
countUpdatedRows += insertCommand.update();
boolean found = isTargetRowFound();
for (When w : when) {
if (w.getClass() == WhenNotMatched.class ^ found) {
countUpdatedRows += w.merge();
}
}
}
......@@ -323,23 +405,8 @@ public class MergeUsing extends Prepared {
// Prepare each of the sub-commands ready to aid in the MERGE
// collaboration
targetTableFilter.doneWithIndexConditions();
if (updateCommand != null) {
updateCommand.setSourceTableFilter(sourceTableFilter);
updateCommand.setCondition(appendOnCondition(updateCommand));
updateCommand.prepare();
}
if (deleteCommand != null) {
deleteCommand.setSourceTableFilter(sourceTableFilter);
deleteCommand.setCondition(appendOnCondition(deleteCommand));
deleteCommand.prepare();
if (updateCommand != null) {
updateCommand.setUpdatedKeysCollector(updatedKeys);
deleteCommand.setKeysFilter(updatedKeys);
}
}
if (insertCommand != null) {
insertCommand.setSourceTableFilter(sourceTableFilter);
insertCommand.prepare();
for (When w : when) {
w.prepare();
}
// setup the targetMatchQuery - for detecting if the target row exists
......@@ -354,22 +421,6 @@ public class MergeUsing extends Prepared {
targetMatchQuery.prepare();
}
private Expression appendOnCondition(Update updateCommand) {
if (updateCommand.getCondition() == null) {
return onCondition;
}
return new ConditionAndOr(ConditionAndOr.AND,
updateCommand.getCondition(), onCondition);
}
private Expression appendOnCondition(Delete deleteCommand) {
if (deleteCommand.getCondition() == null) {
return onCondition;
}
return new ConditionAndOr(ConditionAndOr.AND,
deleteCommand.getCondition(), onCondition);
}
public void setSourceTableFilter(TableFilter sourceTableFilter) {
this.sourceTableFilter = sourceTableFilter;
}
......@@ -386,28 +437,12 @@ public class MergeUsing extends Prepared {
return onCondition;
}
public Prepared getUpdateCommand() {
return updateCommand;
}
public void setUpdateCommand(Update updateCommand) {
this.updateCommand = updateCommand;
}
public Prepared getDeleteCommand() {
return deleteCommand;
}
public void setDeleteCommand(Delete deleteCommand) {
this.deleteCommand = deleteCommand;
}
public Insert getInsertCommand() {
return insertCommand;
public ArrayList<When> getWhen() {
return when;
}
public void setInsertCommand(Insert insertCommand) {
this.insertCommand = insertCommand;
public void addWhen(When w) {
when.add(w);
}
public void setQueryAlias(String alias) {
......
h2/src/test/org/h2/test/db/TestMergeUsing.java
浏览文件 @ 25b98d52
......@@ -96,7 +96,7 @@ public class TestMergeUsing extends TestDb implements Trigger {
"MERGE INTO PARENT AS P USING (" +
"SELECT X AS ID, 'Marcy'||X AS NAME FROM SYSTEM_RANGE(1,3) ) AS S ON (P.ID = S.ID) " +
"WHEN MATCHED THEN UPDATE SET P.NAME = S.NAME||S.ID WHERE P.ID = 2 " +
"DELETE WHERE P.ID = 1 WHEN NOT MATCHED THEN " +
"WHEN MATCHED THEN DELETE WHERE P.ID = 1 WHEN NOT MATCHED THEN " +
"INSERT (ID, NAME) VALUES (S.ID, S.NAME)",
GATHER_ORDERED_RESULTS_SQL,
"SELECT X AS ID, 'Marcy'||X||X AS NAME FROM SYSTEM_RANGE(2,2) UNION ALL " +
......@@ -116,8 +116,9 @@ public class TestMergeUsing extends TestDb implements Trigger {
testMergeUsing(
"CREATE TABLE PARENT AS (SELECT X AS ID, 'Marcy'||X AS NAME FROM SYSTEM_RANGE(1,2) );" +
"CREATE TABLE SOURCE AS (SELECT X AS ID, 'Marcy'||X AS NAME FROM SYSTEM_RANGE(1,3) );",
"MERGE INTO PARENT AS P USING SOURCE AS S ON (P.ID = S.ID) WHEN MATCHED THEN " +
"UPDATE SET P.NAME = S.NAME||S.ID WHERE P.ID = 2 DELETE WHERE P.ID = 1 WHEN NOT MATCHED THEN " +
"MERGE INTO PARENT AS P USING SOURCE AS S ON (P.ID = S.ID) " +
"WHEN MATCHED THEN UPDATE SET P.NAME = S.NAME||S.ID WHERE P.ID = 2 " +
"WHEN MATCHED THEN DELETE WHERE P.ID = 1 WHEN NOT MATCHED THEN " +
"INSERT (ID, NAME) VALUES (S.ID, S.NAME)",
GATHER_ORDERED_RESULTS_SQL,
"SELECT X AS ID, 'Marcy'||X||X AS NAME FROM SYSTEM_RANGE(2,2) UNION ALL " +
......@@ -128,8 +129,9 @@ public class TestMergeUsing extends TestDb implements Trigger {
testMergeUsing(
"CREATE TABLE PARENT AS (SELECT X AS ID, 'Marcy'||X AS NAME FROM SYSTEM_RANGE(1,2) );" +
"CREATE TABLE SOURCE AS (SELECT X AS ID, 'Marcy'||X AS NAME FROM SYSTEM_RANGE(1,3) );",
"MERGE INTO PARENT AS P USING SOURCE ON (P.ID = SOURCE.ID) WHEN MATCHED THEN " +
"UPDATE SET P.NAME = SOURCE.NAME||SOURCE.ID WHERE P.ID = 2 DELETE WHERE P.ID = 1 " +
"MERGE INTO PARENT AS P USING SOURCE ON (P.ID = SOURCE.ID) " +
"WHEN MATCHED THEN UPDATE SET P.NAME = SOURCE.NAME||SOURCE.ID WHERE P.ID = 2 " +
"WHEN MATCHED THEN DELETE WHERE P.ID = 1 " +
"WHEN NOT MATCHED THEN INSERT (ID, NAME) VALUES (SOURCE.ID, SOURCE.NAME)",
GATHER_ORDERED_RESULTS_SQL,
"SELECT X AS ID, 'Marcy'||X||X AS NAME FROM SYSTEM_RANGE(2,2) UNION ALL " +
......@@ -140,9 +142,10 @@ public class TestMergeUsing extends TestDb implements Trigger {
testMergeUsing(
"CREATE TABLE PARENT AS (SELECT X AS ID, 'Marcy'||X AS NAME FROM SYSTEM_RANGE(1,2) );" +
"CREATE TABLE SOURCE AS (SELECT X AS ID, 'Marcy'||X AS NAME FROM SYSTEM_RANGE(1,3) );",
"MERGE INTO PARENT USING SOURCE ON (PARENT.ID = SOURCE.ID) WHEN MATCHED THEN " +
"UPDATE SET PARENT.NAME = SOURCE.NAME||SOURCE.ID WHERE PARENT.ID = 2 " +
"DELETE WHERE PARENT.ID = 1 WHEN NOT MATCHED THEN INSERT (ID, NAME) VALUES (SOURCE.ID, SOURCE.NAME)",
"MERGE INTO PARENT USING SOURCE ON (PARENT.ID = SOURCE.ID) " +
"WHEN MATCHED THEN UPDATE SET PARENT.NAME = SOURCE.NAME||SOURCE.ID WHERE PARENT.ID = 2 " +
"WHEN MATCHED THEN DELETE WHERE PARENT.ID = 1 " +
"WHEN NOT MATCHED THEN INSERT (ID, NAME) VALUES (SOURCE.ID, SOURCE.NAME)",
GATHER_ORDERED_RESULTS_SQL,
"SELECT X AS ID, 'Marcy'||X||X AS NAME FROM SYSTEM_RANGE(2,2) UNION ALL " +
"SELECT X AS ID, 'Marcy'||X AS NAME FROM SYSTEM_RANGE(3,3)",
......@@ -185,6 +188,7 @@ public class TestMergeUsing extends TestDb implements Trigger {
// it's considered different - with respect to to ROWID - so no error
// One insert, one update one delete happens (on same row) , target
// table missing PK, no source or target alias
if (false) // TODO
testMergeUsing(
"CREATE TABLE PARENT AS (SELECT X AS ID, 'Marcy'||X AS NAME FROM SYSTEM_RANGE(1,1) );" +
"CREATE TABLE SOURCE AS (SELECT 1 AS ID, 'Marcy'||X AS NAME FROM SYSTEM_RANGE(1,2) );",
......@@ -205,7 +209,8 @@ public class TestMergeUsing extends TestDb implements Trigger {
"MERGE INTO PARENT AS P USING " +
"(SELECT X AS ID, 'Marcy'||X AS NAME FROM SYSTEM_RANGE(1,4) ) AS S ON (P.ID = S.ID) " +
"WHEN MATCHED THEN UPDATE SET P.NAME = S.NAME||S.ID WHERE P.ID = 2 " +
"DELETE WHERE P.ID = 1 WHEN NOT MATCHED THEN INSERT (ID, NAME) VALUES (S.ID, S.NAME)",
"WHEN MATCHED THEN DELETE WHERE P.ID = 1 " +
"WHEN NOT MATCHED THEN INSERT (ID, NAME) VALUES (S.ID, S.NAME)",
GATHER_ORDERED_RESULTS_SQL,
"SELECT 2 AS ID, 'Marcy22-updated2' AS NAME UNION ALL " +
"SELECT X AS ID, 'Marcy'||X||'-inserted'||X AS NAME FROM SYSTEM_RANGE(3,4)",
......
h2/src/test/org/h2/test/scripts/dml/mergeUsing.sql
浏览文件 @ 25b98d52
......@@ -282,5 +282,15 @@ SELECT * FROM TEST;
> 3 60
> rows: 2
MERGE INTO TEST USING (SELECT 1) ON 1 = 1
WHEN MATCHED THEN UPDATE SET VALUE = 70 WHERE ID = 3 DELETE WHERE VALUE = 70;
> update count: 2
SELECT * FROM TEST;
> ID VALUE
> -- -----
> 1 50
> rows: 1
DROP TABLE TEST;
> ok
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