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h2database
提交 8dd0a0b1 authored 作者: Andrei Tokar's avatar Andrei Tokar
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Merge remote-tracking branch 'h2database/master' into issue_1479 

# Conflicts:
#	h2/src/main/org/h2/command/dml/Delete.java
#	h2/src/main/org/h2/command/dml/Update.java
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h2/src/docsrc/help/help.csv
浏览文件 @ 8dd0a0b1
......@@ -82,7 +82,7 @@ UPDATE PERSON P SET NAME=(SELECT A.NAME FROM ADDRESS A WHERE A.ID=P.ID);
"
"Commands (DML)","DELETE","
DELETE [ TOP term ] FROM tableName deleteSearchCondition
DELETE [ TOP term ] FROM tableName [ WHERE expression ] [ LIMIT term ]
","
Deletes rows form a table.
If TOP or LIMIT is specified, at most the specified number of rows are deleted (no limit if null or smaller than zero).
......@@ -137,36 +137,34 @@ 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'
DELETE WHERE T.COL2='FINAL'
WHEN MATCHED AND T.COL2 <> 'FINAL' THEN
UPDATE SET T.COL1 = S.COL1
WHEN MATCHED AND T.COL2 = 'FINAL' THEN
DELETE
WHEN NOT MATCHED THEN
INSERT (ID,COL1,COL2) VALUES(S.ID,S.COL1,S.COL2)
INSERT (ID, COL1, COL2) VALUES(S.ID, S.COL1, S.COL2)
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'
DELETE WHERE T.COL2='FINAL'
WHEN MATCHED AND T.COL2 <> 'FINAL' THEN
UPDATE SET T.COL1 = S.COL1
WHEN MATCHED AND T.COL2 = 'FINAL' THEN
DELETE
WHEN NOT MATCHED THEN
INSERT (ID,COL1,COL2) VALUES(S.ID,S.COL1,S.COL2)
INSERT VALUES (S.ID, S.COL1, S.COL2)
MERGE INTO TARGET_TABLE USING DUAL ON ID = 1
WHEN NOT MATCHED THEN INSERT (ID, NAME) VALUES (1, 'Test')
WHEN NOT MATCHED THEN INSERT VALUES (1, 'Test')
WHEN MATCHED THEN UPDATE SET NAME = 'Test'
"
......@@ -2277,14 +2275,6 @@ SELECT CAST(0 AS DOUBLE)
SELECT -1.4e-10
"
"Other Grammar","Delete search condition","
[ WHERE expression ] [ LIMIT term ]
","
Search condition for DELETE statement.
","
WHERE ID = 2
"
"Other Grammar","Digit","
0-9
","
......@@ -2373,6 +2363,38 @@ 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 [ AND expression ] THEN
UPDATE SET setClauseList
| DELETE
| {UPDATE SET setClauseList [ WHERE expression ] DELETE [ WHERE expression ]}
","
WHEN MATCHED clause for MERGE USING command.
If both UPDATE and DELETE are specified, DELETE can delete only rows that were updated,
WHERE condition in DELETE clause 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 [ AND expression ] 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
","
......@@ -2496,8 +2518,8 @@ START WITH 1
"
"Other Grammar","Set clause list","
{ { columnName = { DEFAULT | expression } } [,...] } |
{ ( columnName [,...] ) = ( select ) }
{ { columnName = { DEFAULT | expression } } [,...] }
| { ( columnName [,...] ) = ( select ) }
","
List of SET clauses.
","
......
h2/src/docsrc/html/changelog.html
浏览文件 @ 8dd0a0b1
......@@ -21,6 +21,8 @@ Change Log
<h2>Next Version (unreleased)</h2>
<ul>
<li>Issue #1495: MERGE statement doesn't affect any rows when Oracle UPDATE .. WHERE .. DELETE .. WHERE is used
</li>
<li>Issue #1493: MERGE statement fails when it updates more than one row
</li>
<li>Issue #1492: Unnecessary restriction on MERGE USING statement when ON clause doesn't reference any target table columns
......@@ -29,6 +31,8 @@ Change Log
</li>
<li>Issue #1490: NullPointerException when running invalid MERGE statement
</li>
<li>Issue #1489: MERGE USING documentation has misleading railroad diagram
</li>
<li>Issue #1488: Improve documentation of window and some other functions
</li>
<li>Issue #1485: Default window frame in presence of ORDER BY is RANGE .., not ROWS
......
h2/src/main/org/h2/command/Parser.java
浏览文件 @ 8dd0a0b1
......@@ -1116,11 +1116,11 @@ public class Parser {
int start = lastParseIndex;
TableFilter filter = readSimpleTableFilter(0, null);
command.setTableFilter(filter);
parseUpdateSetClause(command, filter, start);
parseUpdateSetClause(command, filter, start, true);
return command;
}
private void parseUpdateSetClause(Update command, TableFilter filter, int start) {
private void parseUpdateSetClause(Update command, TableFilter filter, int start, boolean allowExtensions) {
read("SET");
if (readIf(OPEN_PAREN)) {
ArrayList<Column> columns = Utils.newSmallArrayList();
......@@ -1154,15 +1154,17 @@ public class Parser {
Expression condition = readExpression();
command.setCondition(condition);
}
if (readIf(ORDER)) {
// for MySQL compatibility
// (this syntax is supported, but ignored)
read("BY");
parseSimpleOrderList();
}
if (readIf(LIMIT)) {
Expression limit = readTerm().optimize(session);
command.setLimit(limit);
if (allowExtensions) {
if (readIf(ORDER)) {
// for MySQL compatibility
// (this syntax is supported, but ignored)
read("BY");
parseSimpleOrderList();
}
if (readIf(LIMIT)) {
Expression limit = readTerm().optimize(session);
command.setLimit(limit);
}
}
setSQL(command, "UPDATE", start);
}
......@@ -1197,20 +1199,15 @@ public class Parser {
}
TableFilter filter = readSimpleTableFilter(0, null);
command.setTableFilter(filter);
parseDeleteGivenTable(command, limit, start);
return command;
}
private void parseDeleteGivenTable(Delete command, Expression limit, int start) {
if (readIf(WHERE)) {
Expression condition = readExpression();
command.setCondition(condition);
command.setCondition(readExpression());
}
if (readIf(LIMIT) && limit == null) {
if (limit == null && readIf(LIMIT)) {
limit = readTerm().optimize(session);
}
command.setLimit(limit);
setSQL(command, "DELETE", start);
return command;
}
private IndexColumn[] parseIndexColumnList() {
......@@ -1496,47 +1493,47 @@ 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;
}
private void parseWhenMatched(MergeUsing command) {
Expression and = readIf("AND") ? readExpression() : null;
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;
parseUpdateSetClause(updateCommand, filter, startMatched, false);
startMatched = lastParseIndex;
}
startMatched = lastParseIndex;
Delete deleteCommand = null;
if (readIf("DELETE")) {
Delete deleteCommand = new Delete(session);
TableFilter filter = command.getTargetTableFilter();
deleteCommand.setTableFilter(filter);
parseDeleteGivenTable(deleteCommand, null, startMatched);
command.setDeleteCommand(deleteCommand);
ok = true;
}
if (!ok) {
deleteCommand = new Delete(session);
deleteCommand.setTableFilter(command.getTargetTableFilter());
if (readIf(WHERE)) {
deleteCommand.setCondition(readExpression());
}
setSQL(deleteCommand, "DELETE", startMatched);
}
if (updateCommand != null || deleteCommand != null) {
MergeUsing.WhenMatched when = new MergeUsing.WhenMatched(command);
when.setAndCondition(and);
when.setUpdateCommand(updateCommand);
when.setDeleteCommand(deleteCommand);
command.addWhen(when);
} else {
throw getSyntaxError();
}
}
......@@ -1544,12 +1541,16 @@ public class Parser {
private void parseWhenNotMatched(MergeUsing command) {
read(NOT);
read("MATCHED");
Expression and = readIf("AND") ? readExpression() : null;
read("THEN");
if (readIf("INSERT")) {
Insert insertCommand = new Insert(session);
insertCommand.setTable(command.getTargetTable());
parseInsertGivenTable(insertCommand, command.getTargetTable());
command.setInsertCommand(insertCommand);
MergeUsing.WhenNotMatched when = new MergeUsing.WhenNotMatched(command);
when.setAndCondition(and);
when.setInsertCommand(insertCommand);
command.addWhen(when);
} else {
throw getSyntaxError();
}
......
h2/src/main/org/h2/command/dml/Delete.java
浏览文件 @ 8dd0a0b1
......@@ -5,6 +5,8 @@
*/
package org.h2.command.dml;
import java.util.HashSet;
import org.h2.api.Trigger;
import org.h2.command.CommandInterface;
import org.h2.command.Prepared;
......@@ -40,6 +42,8 @@ public class Delete extends Prepared {
*/
private TableFilter sourceTableFilter;
private HashSet<Long> keysFilter;
public Delete(Session session) {
super(session);
}
......@@ -56,6 +60,15 @@ public class Delete extends Prepared {
return this.condition;
}
/**
* Sets the keys filter.
*
* @param keysFilter the keys filter
*/
public void setKeysFilter(HashSet<Long> keysFilter) {
this.keysFilter = keysFilter;
}
@Override
public int update() {
targetTableFilter.startQuery(session);
......@@ -79,21 +92,23 @@ public class Delete extends Prepared {
setCurrentRowNumber(rows.size() + 1);
if (condition == null || condition.getBooleanValue(session)) {
Row row = targetTableFilter.get();
boolean done = false;
if (table.fireRow()) {
done = table.fireBeforeRow(session, row, null);
}
if (!done) {
if (table.isMVStore()) {
done = table.lockRow(session, row) == null;
if (keysFilter == null || keysFilter.contains(row.getKey())) {
boolean done = false;
if (table.fireRow()) {
done = table.fireBeforeRow(session, row, null);
}
if (!done) {
rows.add(row);
if (table.isMVStore()) {
done = table.lockRow(session, row) == null;
}
if (!done) {
rows.add(row);
}
}
count++;
if (limitRows >= 0 && count >= limitRows) {
break;
}
}
count++;
if (limitRows >= 0 && count >= limitRows) {
break;
}
}
}
......
h2/src/main/org/h2/command/dml/Update.java
浏览文件 @ 8dd0a0b1
......@@ -7,6 +7,7 @@ package org.h2.command.dml;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Objects;
import org.h2.api.ErrorCode;
......@@ -53,6 +54,8 @@ public class Update extends Prepared {
private final ArrayList<Column> columns = Utils.newSmallArrayList();
private final HashMap<Column, Expression> expressionMap = new HashMap<>();
private HashSet<Long> updatedKeysCollector;
public Update(Session session) {
super(session);
}
......@@ -88,6 +91,15 @@ public class Update extends Prepared {
}
}
/**
* Sets the collector of updated keys.
*
* @param updatedKeysCollector the collector of updated keys
*/
public void setUpdatedKeysCollector(HashSet<Long> updatedKeysCollector) {
this.updatedKeysCollector = updatedKeysCollector;
}
@Override
public int update() {
targetTableFilter.startQuery(session);
......@@ -135,7 +147,8 @@ public class Update extends Prepared {
}
newRow.setValue(i, newValue);
}
newRow.setKey(oldRow.getKey());
long key = oldRow.getKey();
newRow.setKey(key);
if (setOnUpdate || updateToCurrentValuesReturnsZero) {
setOnUpdate = false;
for (int i = 0; i < columnCount; i++) {
......@@ -170,6 +183,9 @@ public class Update extends Prepared {
if (!done) {
rows.add(oldRow);
rows.add(newRow);
if (updatedKeysCollector != null) {
updatedKeysCollector.add(key);
}
}
}
count++;
......
h2/src/main/org/h2/table/TableFilter.java
浏览文件 @ 8dd0a0b1
......@@ -82,6 +82,11 @@ public class TableFilter implements ColumnResolver {
*/
private final ArrayList<IndexCondition> indexConditions = Utils.newSmallArrayList();
/**
* Whether new window conditions should not be accepted.
*/
private boolean doneWithIndexConditions;
/**
* Additional conditions that can't be used for index lookup, but for row
* filter for this table (ID=ID, NAME LIKE '%X%')
......@@ -627,7 +632,16 @@ public class TableFilter implements ColumnResolver {
* @param condition the index condition
*/
public void addIndexCondition(IndexCondition condition) {
indexConditions.add(condition);
if (!doneWithIndexConditions) {
indexConditions.add(condition);
}
}
/**
* Used to reject all additional index conditions.
*/
public void doneWithIndexConditions() {
this.doneWithIndexConditions = true;
}
/**
......
h2/src/test/org/h2/test/db/TestMergeUsing.java
浏览文件 @ 8dd0a0b1
......@@ -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 @ 8dd0a0b1
......@@ -29,7 +29,7 @@ EXPLAIN PLAN
UPDATE SET P.NAME = S.NAME WHERE 2 = 2 WHEN NOT
MATCHED THEN
INSERT (ID, NAME) VALUES (S.ID, S.NAME);
>> MERGE INTO PUBLIC.PARENT(ID, NAME) SELECT X AS ID, ('Coco' || X) AS NAME FROM SYSTEM_RANGE(1, 2) /* PUBLIC.RANGE_INDEX */
>> MERGE INTO PUBLIC.PARENT USING SELECT X AS ID, ('Coco' || X) AS NAME FROM SYSTEM_RANGE(1, 2) /* PUBLIC.RANGE_INDEX */
DROP TABLE PARENT;
> ok
......@@ -259,5 +259,66 @@ SELECT * FROM TEST;
> 3 50
> rows: 3
MERGE INTO TEST USING (SELECT 1) ON 1 = 1
WHEN MATCHED THEN UPDATE SET VALUE = 60 WHERE ID = 3 DELETE WHERE ID = 2;
> update count: 1
SELECT * FROM TEST;
> ID VALUE
> -- -----
> 1 50
> 2 50
> 3 60
> rows: 3
MERGE INTO TEST USING (SELECT 1) ON 1 = 1
WHEN MATCHED THEN DELETE WHERE ID = 2;
> update count: 1
SELECT * FROM TEST;
> ID VALUE
> -- -----
> 1 50
> 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
CREATE TABLE T(ID INT, F BOOLEAN, VALUE INT);
> ok
INSERT INTO T VALUES (1, FALSE, 10), (2, TRUE, 20);
> update count: 2
CREATE TABLE S(S_ID INT, S_F BOOLEAN, S_VALUE INT);
> ok
INSERT INTO S VALUES (1, FALSE, 100), (2, TRUE, 200), (3, FALSE, 300), (4, TRUE, 400);
> update count: 4
MERGE INTO T USING S ON ID = S_ID
WHEN MATCHED AND F THEN UPDATE SET VALUE = S_VALUE
WHEN MATCHED AND NOT F THEN DELETE
WHEN NOT MATCHED AND S_F THEN INSERT VALUES (S_ID, S_F, S_VALUE);
> update count: 3
SELECT * FROM T;
> ID F VALUE
> -- ---- -----
> 2 TRUE 200
> 4 TRUE 400
> rows: 2
DROP TABLE T, S;
> ok
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