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The following commit(s) were added to refs/heads/master by this push:
new d8181cf9b6f Add MySQLSelectAdminExecutorFactory (#36849)
d8181cf9b6f is described below
commit d8181cf9b6ff6b20063042394aad590bfbb504d3
Author: Liang Zhang <[email protected]>
AuthorDate: Sat Oct 11 19:03:59 2025 +0800
Add MySQLSelectAdminExecutorFactory (#36849)
* Add MySQLSelectAdminExecutorFactory
* Add MySQLSelectAdminExecutorFactory
---
.../handler/admin/MySQLAdminExecutorCreator.java | 97 +-------------------
.../MySQLInformationSchemaExecutorFactory.java | 2 +-
.../MySQLMySQLSchemaExecutorFactory.java | 2 +-
.../MySQLPerformanceSchemaExecutorFactory.java | 2 +-
.../factory/MySQLSelectAdminExecutorFactory.java | 70 +++++++++++++++
...MySQLSelectWithoutFromAdminExecutorFactory.java | 100 +++++++++++++++++++++
.../MySQLSysSchemaExecutorFactory.java | 2 +-
7 files changed, 176 insertions(+), 99 deletions(-)
diff --git
a/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/MySQLAdminExecutorCreator.java
b/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/MySQLAdminExecutorCreator.java
index ff6584798b7..3c9cca998d1 100644
---
a/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/MySQLAdminExecutorCreator.java
+++
b/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/MySQLAdminExecutorCreator.java
@@ -19,30 +19,20 @@ package
org.apache.shardingsphere.proxy.backend.mysql.handler.admin;
import
org.apache.shardingsphere.infra.binder.context.statement.SQLStatementContext;
import
org.apache.shardingsphere.infra.binder.context.statement.type.dml.SelectStatementContext;
-import org.apache.shardingsphere.proxy.backend.context.ProxyContext;
import
org.apache.shardingsphere.proxy.backend.handler.admin.executor.DatabaseAdminExecutor;
import
org.apache.shardingsphere.proxy.backend.handler.admin.executor.DatabaseAdminExecutorCreator;
import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.KillProcessExecutor;
import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.MySQLSetVariableAdminExecutor;
-import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.MySQLSystemVariableQueryExecutor;
-import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.NoResourceShowExecutor;
-import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.ShowConnectionIdExecutor;
import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.ShowCreateDatabaseExecutor;
-import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.ShowCurrentDatabaseExecutor;
-import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.ShowCurrentUserExecutor;
import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.ShowDatabasesExecutor;
import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.ShowFunctionStatusExecutor;
import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.ShowProcedureStatusExecutor;
import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.ShowProcessListExecutor;
import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.ShowTablesExecutor;
-import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.ShowVersionExecutor;
-import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.UnicastResourceShowExecutor;
import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.UseDatabaseExecutor;
-import
org.apache.shardingsphere.sql.parser.statement.core.segment.dml.item.ExpressionProjectionSegment;
-import
org.apache.shardingsphere.sql.parser.statement.core.segment.dml.item.ProjectionSegment;
+import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.factory.MySQLSelectAdminExecutorFactory;
import
org.apache.shardingsphere.sql.parser.statement.core.statement.SQLStatement;
import
org.apache.shardingsphere.sql.parser.statement.core.statement.type.dal.SetStatement;
-import
org.apache.shardingsphere.sql.parser.statement.core.statement.type.dml.SelectStatement;
import
org.apache.shardingsphere.sql.parser.statement.mysql.dal.MySQLKillStatement;
import
org.apache.shardingsphere.sql.parser.statement.mysql.dal.MySQLUseStatement;
import
org.apache.shardingsphere.sql.parser.statement.mysql.dal.show.database.MySQLShowCreateDatabaseStatement;
@@ -52,8 +42,6 @@ import
org.apache.shardingsphere.sql.parser.statement.mysql.dal.show.procedure.M
import
org.apache.shardingsphere.sql.parser.statement.mysql.dal.show.process.MySQLShowProcessListStatement;
import
org.apache.shardingsphere.sql.parser.statement.mysql.dal.show.table.MySQLShowTablesStatement;
-import java.util.Collection;
-import java.util.Iterator;
import java.util.List;
import java.util.Optional;
@@ -62,18 +50,10 @@ import java.util.Optional;
*/
public final class MySQLAdminExecutorCreator implements
DatabaseAdminExecutorCreator {
- private static final String INFORMATION_SCHEMA = "information_schema";
-
- private static final String MYSQL_SCHEMA = "mysql";
-
- private static final String PERFORMANCE_SCHEMA = "performance_schema";
-
- private static final String SYS_SCHEMA = "sys";
-
@Override
public Optional<DatabaseAdminExecutor> create(final SQLStatementContext
sqlStatementContext, final String sql, final String databaseName, final
List<Object> parameters) {
if (sqlStatementContext instanceof SelectStatementContext) {
- return createExecutorForSelectStatement((SelectStatementContext)
sqlStatementContext, sql, databaseName, parameters);
+ return
MySQLSelectAdminExecutorFactory.newInstance((SelectStatementContext)
sqlStatementContext, sql, databaseName, parameters);
}
SQLStatement sqlStatement = sqlStatementContext.getSqlStatement();
if (sqlStatement instanceof MySQLUseStatement) {
@@ -106,79 +86,6 @@ public final class MySQLAdminExecutorCreator implements
DatabaseAdminExecutorCre
return Optional.empty();
}
- private Optional<DatabaseAdminExecutor>
createExecutorForSelectStatement(final SelectStatementContext
selectStatementContext, final String sql,
-
final String databaseName, final List<Object> parameters) {
- if (!selectStatementContext.getSqlStatement().getFrom().isPresent()) {
- return
findAdminExecutorForSelectWithoutFrom(selectStatementContext.getSqlStatement(),
sql, databaseName);
- }
- if (INFORMATION_SCHEMA.equalsIgnoreCase(databaseName) &&
!ProxyContext.getInstance().getContextManager().getDatabase(databaseName).isComplete())
{
- return
MySQLInformationSchemaExecutorFactory.newInstance(selectStatementContext, sql,
parameters);
- }
- if (PERFORMANCE_SCHEMA.equalsIgnoreCase(databaseName) &&
!ProxyContext.getInstance().getContextManager().getDatabase(databaseName).isComplete())
{
- return
MySQLPerformanceSchemaExecutorFactory.newInstance(selectStatementContext, sql,
parameters);
- }
- if (MYSQL_SCHEMA.equalsIgnoreCase(databaseName) &&
!ProxyContext.getInstance().getContextManager().getDatabase(databaseName).isComplete())
{
- return
MySQLMySQLSchemaExecutorFactory.newInstance(selectStatementContext, sql,
parameters);
- }
- if (SYS_SCHEMA.equalsIgnoreCase(databaseName) &&
!ProxyContext.getInstance().getContextManager().getDatabase(databaseName).isComplete())
{
- return
MySQLSysSchemaExecutorFactory.newInstance(selectStatementContext, sql,
parameters);
- }
- return Optional.empty();
- }
-
- private Optional<DatabaseAdminExecutor>
findAdminExecutorForSelectWithoutFrom(final SelectStatement selectStatement,
final String sql, final String databaseName) {
- Optional<DatabaseAdminExecutor> result =
MySQLSystemVariableQueryExecutor.tryGetSystemVariableQueryExecutor(selectStatement);
- return result.isPresent() ? result :
getSelectFunctionOrVariableExecutor(selectStatement, sql, databaseName);
- }
-
- private Optional<DatabaseAdminExecutor>
getSelectFunctionOrVariableExecutor(final SelectStatement selectStatement,
final String sql, final String databaseName) {
- if (isShowSpecialFunction(selectStatement,
ShowConnectionIdExecutor.FUNCTION_NAME)) {
- return Optional.of(new ShowConnectionIdExecutor(selectStatement));
- }
- if (isShowSpecialFunction(selectStatement,
ShowVersionExecutor.FUNCTION_NAME)) {
- return Optional.of(new ShowVersionExecutor(selectStatement));
- }
- if (isShowSpecialFunction(selectStatement,
ShowCurrentUserExecutor.FUNCTION_NAME) ||
isShowSpecialFunction(selectStatement,
ShowCurrentUserExecutor.FUNCTION_NAME_ALIAS)) {
- return Optional.of(new ShowCurrentUserExecutor());
- }
- if (isShowSpecialFunction(selectStatement,
ShowCurrentDatabaseExecutor.FUNCTION_NAME)) {
- return Optional.of(new ShowCurrentDatabaseExecutor());
- }
- return mockExecutor(databaseName, selectStatement, sql);
- }
-
- private boolean isShowSpecialFunction(final SelectStatement sqlStatement,
final String functionName) {
- Iterator<ProjectionSegment> segmentIterator =
sqlStatement.getProjections().getProjections().iterator();
- ProjectionSegment firstProjection = segmentIterator.next();
- if (segmentIterator.hasNext() || !(firstProjection instanceof
ExpressionProjectionSegment)) {
- return false;
- }
- String projectionText = ((ExpressionProjectionSegment)
firstProjection).getText();
- String trimmedText = projectionText.replaceAll("\\s+\\(", "(");
- return functionName.equalsIgnoreCase(trimmedText);
- }
-
- private Optional<DatabaseAdminExecutor> mockExecutor(final String
databaseName, final SelectStatement sqlStatement, final String sql) {
- if (hasNoResource()) {
- return Optional.of(new NoResourceShowExecutor(sqlStatement));
- }
- boolean isUseSchema = null != databaseName ||
sqlStatement.getFrom().isPresent();
- return isUseSchema ? Optional.empty() : Optional.of(new
UnicastResourceShowExecutor(sqlStatement, sql));
- }
-
- private boolean hasNoResource() {
- Collection<String> databaseNames =
ProxyContext.getInstance().getContextManager().getAllDatabaseNames();
- if (databaseNames.isEmpty()) {
- return true;
- }
- for (String each : databaseNames) {
- if
(ProxyContext.getInstance().getContextManager().getDatabase(each).containsDataSource())
{
- return false;
- }
- }
- return true;
- }
-
@Override
public String getDatabaseType() {
return "MySQL";
diff --git
a/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/MySQLInformationSchemaExecutorFactory.java
b/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/factory/MySQLInformationSchemaExecutorFactory.java
similarity index 99%
rename from
proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/MySQLInformationSchemaExecutorFactory.java
rename to
proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/factory/MySQLInformationSchemaExecutorFactory.java
index 78817f54f7f..91d5103f369 100644
---
a/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/MySQLInformationSchemaExecutorFactory.java
+++
b/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/factory/MySQLInformationSchemaExecutorFactory.java
@@ -15,7 +15,7 @@
* limitations under the License.
*/
-package org.apache.shardingsphere.proxy.backend.mysql.handler.admin;
+package org.apache.shardingsphere.proxy.backend.mysql.handler.admin.factory;
import lombok.AccessLevel;
import lombok.NoArgsConstructor;
diff --git
a/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/MySQLMySQLSchemaExecutorFactory.java
b/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/factory/MySQLMySQLSchemaExecutorFactory.java
similarity index 99%
rename from
proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/MySQLMySQLSchemaExecutorFactory.java
rename to
proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/factory/MySQLMySQLSchemaExecutorFactory.java
index 1e460c4d4ff..7d1ddfca2f2 100644
---
a/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/MySQLMySQLSchemaExecutorFactory.java
+++
b/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/factory/MySQLMySQLSchemaExecutorFactory.java
@@ -15,7 +15,7 @@
* limitations under the License.
*/
-package org.apache.shardingsphere.proxy.backend.mysql.handler.admin;
+package org.apache.shardingsphere.proxy.backend.mysql.handler.admin.factory;
import lombok.AccessLevel;
import lombok.NoArgsConstructor;
diff --git
a/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/MySQLPerformanceSchemaExecutorFactory.java
b/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/factory/MySQLPerformanceSchemaExecutorFactory.java
similarity index 99%
rename from
proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/MySQLPerformanceSchemaExecutorFactory.java
rename to
proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/factory/MySQLPerformanceSchemaExecutorFactory.java
index fc421c026e3..1079a58d686 100644
---
a/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/MySQLPerformanceSchemaExecutorFactory.java
+++
b/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/factory/MySQLPerformanceSchemaExecutorFactory.java
@@ -15,7 +15,7 @@
* limitations under the License.
*/
-package org.apache.shardingsphere.proxy.backend.mysql.handler.admin;
+package org.apache.shardingsphere.proxy.backend.mysql.handler.admin.factory;
import lombok.AccessLevel;
import lombok.NoArgsConstructor;
diff --git
a/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/factory/MySQLSelectAdminExecutorFactory.java
b/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/factory/MySQLSelectAdminExecutorFactory.java
new file mode 100644
index 00000000000..0576b13fb76
--- /dev/null
+++
b/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/factory/MySQLSelectAdminExecutorFactory.java
@@ -0,0 +1,70 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.shardingsphere.proxy.backend.mysql.handler.admin.factory;
+
+import lombok.AccessLevel;
+import lombok.NoArgsConstructor;
+import
org.apache.shardingsphere.infra.binder.context.statement.type.dml.SelectStatementContext;
+import org.apache.shardingsphere.proxy.backend.context.ProxyContext;
+import
org.apache.shardingsphere.proxy.backend.handler.admin.executor.DatabaseAdminExecutor;
+
+import java.util.List;
+import java.util.Optional;
+
+/**
+ * Select admin executor factory for MySQL.
+ */
+@NoArgsConstructor(access = AccessLevel.PRIVATE)
+public final class MySQLSelectAdminExecutorFactory {
+
+ private static final String INFORMATION_SCHEMA = "information_schema";
+
+ private static final String PERFORMANCE_SCHEMA = "performance_schema";
+
+ private static final String MYSQL_SCHEMA = "mysql";
+
+ private static final String SYS_SCHEMA = "sys";
+
+ /**
+ * New instance of select admin executor for MySQL.
+ *
+ * @param selectStatementContext select statement context
+ * @param sql SQL
+ * @param databaseName database name
+ * @param parameters SQL parameters
+ * @return created instance
+ */
+ public static Optional<DatabaseAdminExecutor> newInstance(final
SelectStatementContext selectStatementContext, final String sql, final String
databaseName, final List<Object> parameters) {
+ if (!selectStatementContext.getSqlStatement().getFrom().isPresent()) {
+ return
MySQLSelectWithoutFromAdminExecutorFactory.newInstance(selectStatementContext,
sql, databaseName);
+ }
+ if (INFORMATION_SCHEMA.equalsIgnoreCase(databaseName) &&
!ProxyContext.getInstance().getContextManager().getDatabase(databaseName).isComplete())
{
+ return
MySQLInformationSchemaExecutorFactory.newInstance(selectStatementContext, sql,
parameters);
+ }
+ if (PERFORMANCE_SCHEMA.equalsIgnoreCase(databaseName) &&
!ProxyContext.getInstance().getContextManager().getDatabase(databaseName).isComplete())
{
+ return
MySQLPerformanceSchemaExecutorFactory.newInstance(selectStatementContext, sql,
parameters);
+ }
+ if (MYSQL_SCHEMA.equalsIgnoreCase(databaseName) &&
!ProxyContext.getInstance().getContextManager().getDatabase(databaseName).isComplete())
{
+ return
MySQLMySQLSchemaExecutorFactory.newInstance(selectStatementContext, sql,
parameters);
+ }
+ if (SYS_SCHEMA.equalsIgnoreCase(databaseName) &&
!ProxyContext.getInstance().getContextManager().getDatabase(databaseName).isComplete())
{
+ return
MySQLSysSchemaExecutorFactory.newInstance(selectStatementContext, sql,
parameters);
+ }
+ return Optional.empty();
+ }
+}
diff --git
a/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/factory/MySQLSelectWithoutFromAdminExecutorFactory.java
b/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/factory/MySQLSelectWithoutFromAdminExecutorFactory.java
new file mode 100644
index 00000000000..8b22c653d70
--- /dev/null
+++
b/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/factory/MySQLSelectWithoutFromAdminExecutorFactory.java
@@ -0,0 +1,100 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.shardingsphere.proxy.backend.mysql.handler.admin.factory;
+
+import lombok.AccessLevel;
+import lombok.NoArgsConstructor;
+import
org.apache.shardingsphere.infra.binder.context.statement.type.dml.SelectStatementContext;
+import
org.apache.shardingsphere.infra.metadata.database.ShardingSphereDatabase;
+import org.apache.shardingsphere.proxy.backend.context.ProxyContext;
+import
org.apache.shardingsphere.proxy.backend.handler.admin.executor.DatabaseAdminExecutor;
+import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.MySQLSystemVariableQueryExecutor;
+import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.NoResourceShowExecutor;
+import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.ShowConnectionIdExecutor;
+import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.ShowCurrentDatabaseExecutor;
+import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.ShowCurrentUserExecutor;
+import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.ShowVersionExecutor;
+import
org.apache.shardingsphere.proxy.backend.mysql.handler.admin.executor.UnicastResourceShowExecutor;
+import
org.apache.shardingsphere.sql.parser.statement.core.segment.dml.item.ExpressionProjectionSegment;
+import
org.apache.shardingsphere.sql.parser.statement.core.segment.dml.item.ProjectionSegment;
+import
org.apache.shardingsphere.sql.parser.statement.core.statement.type.dml.SelectStatement;
+
+import java.util.Collection;
+import java.util.Iterator;
+import java.util.Optional;
+
+/**
+ * Select without from admin executor factory for MySQL.
+ */
+@NoArgsConstructor(access = AccessLevel.PRIVATE)
+public final class MySQLSelectWithoutFromAdminExecutorFactory {
+
+ /**
+ * New instance of select without from admin executor factory for MySQL.
+ *
+ * @param selectStatementContext select statement context
+ * @param sql SQL
+ * @param databaseName database name
+ * @return created instance
+ */
+ public static Optional<DatabaseAdminExecutor> newInstance(final
SelectStatementContext selectStatementContext, final String sql, final String
databaseName) {
+ SelectStatement selectStatement =
selectStatementContext.getSqlStatement();
+ Optional<DatabaseAdminExecutor> result =
MySQLSystemVariableQueryExecutor.tryGetSystemVariableQueryExecutor(selectStatement);
+ return result.isPresent() ? result :
getSelectFunctionOrVariableExecutor(selectStatement, sql, databaseName);
+ }
+
+ private static Optional<DatabaseAdminExecutor>
getSelectFunctionOrVariableExecutor(final SelectStatement selectStatement,
final String sql, final String databaseName) {
+ if (isShowSpecialFunction(selectStatement,
ShowConnectionIdExecutor.FUNCTION_NAME)) {
+ return Optional.of(new ShowConnectionIdExecutor(selectStatement));
+ }
+ if (isShowSpecialFunction(selectStatement,
ShowVersionExecutor.FUNCTION_NAME)) {
+ return Optional.of(new ShowVersionExecutor(selectStatement));
+ }
+ if (isShowSpecialFunction(selectStatement,
ShowCurrentUserExecutor.FUNCTION_NAME) ||
isShowSpecialFunction(selectStatement,
ShowCurrentUserExecutor.FUNCTION_NAME_ALIAS)) {
+ return Optional.of(new ShowCurrentUserExecutor());
+ }
+ if (isShowSpecialFunction(selectStatement,
ShowCurrentDatabaseExecutor.FUNCTION_NAME)) {
+ return Optional.of(new ShowCurrentDatabaseExecutor());
+ }
+ return mockExecutor(databaseName, selectStatement, sql);
+ }
+
+ private static boolean isShowSpecialFunction(final SelectStatement
sqlStatement, final String functionName) {
+ Iterator<ProjectionSegment> segmentIterator =
sqlStatement.getProjections().getProjections().iterator();
+ ProjectionSegment firstProjection = segmentIterator.next();
+ if (segmentIterator.hasNext() || !(firstProjection instanceof
ExpressionProjectionSegment)) {
+ return false;
+ }
+ String projectionText = ((ExpressionProjectionSegment)
firstProjection).getText();
+ String trimmedText = projectionText.replaceAll("\\s+\\(", "(");
+ return functionName.equalsIgnoreCase(trimmedText);
+ }
+
+ private static Optional<DatabaseAdminExecutor> mockExecutor(final String
databaseName, final SelectStatement sqlStatement, final String sql) {
+ if (isEmptyResource()) {
+ return Optional.of(new NoResourceShowExecutor(sqlStatement));
+ }
+ boolean isUseDatabase = null != databaseName ||
sqlStatement.getFrom().isPresent();
+ return isUseDatabase ? Optional.empty() : Optional.of(new
UnicastResourceShowExecutor(sqlStatement, sql));
+ }
+
+ private static boolean isEmptyResource() {
+ Collection<ShardingSphereDatabase> databases =
ProxyContext.getInstance().getContextManager().getMetaDataContexts().getMetaData().getAllDatabases();
+ return databases.isEmpty() ||
databases.stream().noneMatch(ShardingSphereDatabase::containsDataSource);
+ }
+}
diff --git
a/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/MySQLSysSchemaExecutorFactory.java
b/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/factory/MySQLSysSchemaExecutorFactory.java
similarity index 99%
rename from
proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/MySQLSysSchemaExecutorFactory.java
rename to
proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/factory/MySQLSysSchemaExecutorFactory.java
index 0b806283dd3..faee54662b3 100644
---
a/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/MySQLSysSchemaExecutorFactory.java
+++
b/proxy/backend/dialect/mysql/src/main/java/org/apache/shardingsphere/proxy/backend/mysql/handler/admin/factory/MySQLSysSchemaExecutorFactory.java
@@ -15,7 +15,7 @@
* limitations under the License.
*/
-package org.apache.shardingsphere.proxy.backend.mysql.handler.admin;
+package org.apache.shardingsphere.proxy.backend.mysql.handler.admin.factory;
import lombok.AccessLevel;
import lombok.NoArgsConstructor;
