docs(sql): add shared database sharding migrations

2026-09-22 15:19:56 +08:00
parent 2e0612acbb
commit 76b462e334
3 changed files with 561 additions and 0 deletions
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+-- 仅用于本地环境：为 IM 业务表补充 tenant_id 字段。
+--
+-- 本脚本只修改表结构并回填现有数据，不修改索引、唯一约束或应用代码，
+-- 也不会启用多商户共库能力。
+
+USE `tinode`;
+
+DELIMITER $$
+
+DROP PROCEDURE IF EXISTS add_im_tenant_columns$$
+CREATE PROCEDURE add_im_tenant_columns(IN target_schema VARCHAR(64), IN default_tenant_id BIGINT)
+BEGIN
+    DECLARE done INT DEFAULT 0;
+    DECLARE target_table VARCHAR(128);
+    DECLARE has_id INT DEFAULT 0;
+    DECLARE table_cursor CURSOR FOR
+        SELECT t.table_name
+        FROM information_schema.tables t
+        WHERE t.table_schema = target_schema
+          AND t.table_type = 'BASE TABLE'
+          AND t.table_name LIKE 'im\_%'
+          AND NOT EXISTS (
+              SELECT 1
+              FROM information_schema.columns c
+              WHERE c.table_schema = t.table_schema
+                AND c.table_name = t.table_name
+                AND c.column_name = 'tenant_id'
+          );
+    DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = 1;
+
+    OPEN table_cursor;
+    table_loop: LOOP
+        FETCH table_cursor INTO target_table;
+        IF done = 1 THEN
+            LEAVE table_loop;
+        END IF;
+
+        SELECT COUNT(*) INTO has_id
+        FROM information_schema.columns
+        WHERE table_schema = target_schema
+          AND table_name = target_table
+          AND column_name = 'id';
+
+        SET @position_sql = IF(has_id > 0, ' AFTER `id`', ' FIRST');
+        SET @alter_sql = CONCAT(
+            'ALTER TABLE `', target_schema, '`.`', target_table,
+            '` ADD COLUMN `tenant_id` BIGINT NOT NULL DEFAULT ',
+            default_tenant_id,
+            ' COMMENT ''租户ID''',
+            @position_sql
+        );
+        PREPARE alter_stmt FROM @alter_sql;
+        EXECUTE alter_stmt;
+        DEALLOCATE PREPARE alter_stmt;
+    END LOOP;
+    CLOSE table_cursor;
+END$$
+
+DELIMITER ;
+
+-- 本地默认业务库，现有数据归属 tenant_id=1。
+CALL add_im_tenant_columns('tinode', 1);
+
+-- 本地独立业务库，现有数据归属 tenant_id=2。
+CALL add_im_tenant_columns('meeting_im', 2);
+
+DROP PROCEDURE IF EXISTS add_im_tenant_columns;
+
+-- 验证：以下结果中 missing_count 应全部为 0。
+SELECT 'tinode' AS db_name, COUNT(*) AS missing_count
+FROM information_schema.tables t
+WHERE t.table_schema = 'tinode'
+  AND t.table_type = 'BASE TABLE'
+  AND t.table_name LIKE 'im\_%'
+  AND NOT EXISTS (
+      SELECT 1 FROM information_schema.columns c
+      WHERE c.table_schema = t.table_schema
+        AND c.table_name = t.table_name
+        AND c.column_name = 'tenant_id'
+  )
+UNION ALL
+SELECT 'meeting_im', COUNT(*)
+FROM information_schema.tables t
+WHERE t.table_schema = 'meeting_im'
+  AND t.table_type = 'BASE TABLE'
+  AND t.table_name LIKE 'im\_%'
+  AND NOT EXISTS (
+      SELECT 1 FROM information_schema.columns c
+      WHERE c.table_schema = t.table_schema
+        AND c.table_name = t.table_name
+        AND c.column_name = 'tenant_id'
+  );