Add unit tests for JDBCAlarmQueryDAO SQL building

oap-server/server-storage-plugin/storage-jdbc-hikaricp-plugin/src/test/java/org/apache/skywalking/oap/server/storage/plugin/jdbc/common/dao/JDBCAlarmQueryDAOTest.java

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+/*
+ * 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.skywalking.oap.server.storage.plugin.jdbc.common.dao;
+
+import org.apache.skywalking.oap.server.core.alarm.AlarmRecord;
+import org.apache.skywalking.oap.server.core.analysis.manual.searchtag.Tag;
+import org.apache.skywalking.oap.server.core.query.input.Duration;
+import org.apache.skywalking.oap.server.library.client.jdbc.hikaricp.JDBCClient;
+import org.apache.skywalking.oap.server.library.module.ModuleManager;
+import org.apache.skywalking.oap.server.storage.plugin.jdbc.common.JDBCTableInstaller;
+import org.apache.skywalking.oap.server.storage.plugin.jdbc.common.SQLAndParameters;
+import org.apache.skywalking.oap.server.storage.plugin.jdbc.common.TableHelper;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
+
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class JDBCAlarmQueryDAOTest {
+
+    private static final String TABLE = "alarm_record_20260406";
+    private static final String TAG_TABLE = "alarm_record_tag_20260406";
+
+    @Mock
+    private JDBCClient jdbcClient;
+    @Mock
+    private ModuleManager moduleManager;
+    @Mock
+    private TableHelper tableHelper;
+
+    private JDBCAlarmQueryDAO dao;
+
+    @BeforeEach
+    void setUp() {
+        dao = new JDBCAlarmQueryDAO(jdbcClient, moduleManager, tableHelper);
+    }
+
+    @Test
+    void buildSQL_shouldContainTableColumnConditionOnlyOnce() {
+        final SQLAndParameters result = dao.buildSQL(null, null, 10, 0, null, null, TABLE);
+        final String sql = result.sql();
+
+        final long count = countOccurrences(sql, JDBCTableInstaller.TABLE_COLUMN + " = ?");
+        assertThat(count).as("TABLE_COLUMN condition should appear exactly once").isEqualTo(1);
+    }
+
+    @Test
+    void buildSQL_withNoConditions_shouldProduceMinimalQuery() {
+        final SQLAndParameters result = dao.buildSQL(null, null, 10, 0, null, null, TABLE);
+        final String sql = result.sql();
+
+        assertThat(sql).contains("select * from " + TABLE);
+        assertThat(sql).contains("where " + TABLE + "." + JDBCTableInstaller.TABLE_COLUMN + " = ?");
+        assertThat(sql).contains("order by " + AlarmRecord.START_TIME + " desc");
+        assertThat(sql).contains("limit 10");
+        assertThat(sql).doesNotContain("inner join");
+        assertThat(sql).doesNotContain(AlarmRecord.SCOPE);
+        assertThat(sql).doesNotContain("like");
+    }
+
+    @Test
+    void buildSQL_withScopeId_shouldIncludeScopeCondition() {
+        final SQLAndParameters result = dao.buildSQL(1, null, 10, 0, null, null, TABLE);
+        final String sql = result.sql();
+
+        assertThat(sql).contains("and " + AlarmRecord.SCOPE + " = ?");
+        assertThat(result.parameters()).contains(1);
+    }
+
+    @Test
+    void buildSQL_withKeyword_shouldIncludeLikeCondition() {
+        final SQLAndParameters result = dao.buildSQL(null, "error", 10, 0, null, null, TABLE);
+        final String sql = result.sql();
+
+        assertThat(sql).contains("and " + AlarmRecord.ALARM_MESSAGE + " like concat('%',?,'%')");
+        assertThat(result.parameters()).contains("error");
+    }
+
+    @Test
+    void buildSQL_withDuration_shouldIncludeTimeBucketConditions() {
+        final Duration duration = new Duration();
+        duration.setStart("2026-04-06 0000");
+        duration.setEnd("2026-04-06 2359");
+        duration.setStep(org.apache.skywalking.oap.server.core.query.enumeration.Step.MINUTE);
+
+        final SQLAndParameters result = dao.buildSQL(null, null, 10, 0, duration, null, TABLE);
+        final String sql = result.sql();
+
+        assertThat(sql).contains("and " + TABLE + "." + AlarmRecord.TIME_BUCKET + " >= ?");
+        assertThat(sql).contains("and " + TABLE + "." + AlarmRecord.TIME_BUCKET + " <= ?");
+    }
+
+    @Test
+    void buildSQL_withSingleTag_shouldUseInnerJoin() {
+        final List<Tag> tags = Collections.singletonList(new Tag("env", "prod"));
+
+        final SQLAndParameters result = dao.buildSQL(null, null, 10, 0, null, tags, TABLE);
+        final String sql = result.sql();
+
+        assertThat(sql).contains("inner join " + TAG_TABLE + " " + TAG_TABLE + "0");
+        assertThat(sql).contains(TAG_TABLE + "0." + AlarmRecord.TAGS + " = ?");
+        assertThat(result.parameters()).contains("env=prod");
+    }
+
+    @Test
+    void buildSQL_withMultipleTags_shouldUseMultipleInnerJoins() {
+        final List<Tag> tags = Arrays.asList(new Tag("env", "prod"), new Tag("region", "us-east"));
+
+        final SQLAndParameters result = dao.buildSQL(null, null, 10, 0, null, tags, TABLE);
+        final String sql = result.sql();
+
+        assertThat(sql).contains("inner join " + TAG_TABLE + " " + TAG_TABLE + "0");
+        assertThat(sql).contains("inner join " + TAG_TABLE + " " + TAG_TABLE + "1");
+        assertThat(sql).contains(TAG_TABLE + "0." + AlarmRecord.TAGS + " = ?");
+        assertThat(sql).contains(TAG_TABLE + "1." + AlarmRecord.TAGS + " = ?");
+    }
+
+    @Test
+    void buildSQL_withLimitAndOffset_shouldApplyTotalAsLimit() {
+        final SQLAndParameters result = dao.buildSQL(null, null, 20, 5, null, null, TABLE);
+        final String sql = result.sql();
+
+        // JDBC uses offset+limit as the database LIMIT, then skips in application
+        assertThat(sql).contains("limit 25");
+    }
+
+    private long countOccurrences(final String text, final String pattern) {
+        int count = 0;
+        int index = 0;
+        while ((index = text.indexOf(pattern, index)) != -1) {
+            count++;
+            index += pattern.length();
+        }
+        return count;
+    }
+}