docs: add database options 'stt_trigger' and 'tsdb_pagesize'

docs/en/12-taos-sql/02-database.md

@@ -30,8 +30,10 @@ database_option: {
   | WAL_LEVEL {1 | 2}
   | VGROUPS value
   | SINGLE_STABLE {0 | 1}
+  | STT_TRIGGER value
   | TABLE_PREFIX value
   | TABLE_SUFFIX value
+  | TSDB_PAGESIZE value
   | WAL_RETENTION_PERIOD value
   | WAL_ROLL_PERIOD value
   | WAL_RETENTION_SIZE value
@@ -69,8 +71,10 @@ database_option: {
 - SINGLE_STABLE: specifies whether the database can contain more than one supertable.
   - 0: The database can contain multiple supertables.
   - 1: The database can contain only one supertable.
+- STT_TRIGGER: specifies the number of file merges triggered by flushed files. The default is 8, ranging from 1 to 16.
 - TABLE_PREFIX：The prefix length in the table name that is ignored when distributing table to vnode based on table name.
 - TABLE_SUFFIX：The suffix length in the table name that is ignored when distributing table to vnode based on table name.
+- TSDB_PAGESIZE: The page size of the data storage engine in a vnode. The unit is KB. The default is 4 KB. The range is 1 to 16384, that is, 1 KB to 16 MB.
 - WAL_RETENTION_PERIOD: specifies the time after which WAL files are deleted. This parameter is used for data subscription. Enter a time in seconds. The default value of single copy is 0. A value of 0 indicates that each WAL file is deleted immediately after its contents are written to disk. -1: WAL files are never deleted. The default value of multiple copy is 4 days.
 - WAL_RETENTION_SIZE: specifies the size at which WAL files are deleted. This parameter is used for data subscription. Enter a size in KB. The default value of single copy is 0. A value of 0 indicates that each WAL file is deleted immediately after its contents are written to disk. -1: WAL files are never deleted. The default value of multiple copy is -1.
 - WAL_ROLL_PERIOD: specifies the time after which WAL files are rotated. After this period elapses, a new WAL file is created. The default value of single copy is 0. A value of 0 indicates that a new WAL file is created only after the previous WAL file was written to disk. The default values of multiple copy is 1 day.

docs/en/12-taos-sql/06-select.md

@@ -350,9 +350,9 @@ SELECT AVG(CASE WHEN voltage < 200 or voltage > 250 THEN 220 ELSE voltage END) F
 
 ## JOIN
 
-TDengine supports natural joins between supertables, between standard tables, and between subqueries. The difference between natural joins and inner joins is that natural joins require that the fields being joined in the supertables or standard tables must have the same name. Data or tag columns must be joined with the equivalent column in another table.
+TDengine supports the `INTER JOIN` based on the timestamp primary key, that is, the `JOIN` condition must contain the timestamp primary key. As long as the requirement of timestamp-based primary key is met, `INTER JOIN` can be made between normal tables, sub-tables, super tables and sub-queries at will, and there is no limit on the number of tables.
 
-For standard tables, only the timestamp (primary key) can be used in join operations. For example:
+For standard tables:
 
 ```sql
 SELECT *
@@ -360,7 +360,7 @@ FROM temp_tb_1 t1, pressure_tb_1 t2
 WHERE t1.ts = t2.ts
 ```
 
-For supertables, tags as well as timestamps can be used in join operations. For example:
+For supertables:
 
 ```sql
 SELECT *
@@ -368,20 +368,15 @@ FROM temp_stable t1, temp_stable t2
 WHERE t1.ts = t2.ts AND t1.deviceid = t2.deviceid AND t1.status=0;
 ```
 
-Similarly, join operations can be performed on the result sets of multiple subqueries.
-
-:::note
-
-The following restriction apply to JOIN statements:
+For sub-table and super table：
 
-- The number of tables or supertables in a single join operation cannot exceed 10.
-- `FILL` cannot be used in a JOIN statement.
-- Arithmetic operations cannot be performed on the result sets of join operation.
-- `GROUP BY` is not allowed on a segment of the tables that participate in a join operation.
-- `OR` cannot be used in the conditions for join operation
-- Join operation can be performed only on tags or timestamps. You cannot perform a join operation on data columns.
+```sql
+SELECT *
+FROM temp_ctable t1, temp_stable t2
+WHERE t1.ts = t2.ts AND t1.deviceid = t2.deviceid AND t1.status=0;
+```
 
-:::
+Similarly, join operations can be performed on the result sets of multiple subqueries.
 
 ## Nested Query
 

docs/zh/12-taos-sql/02-database.md

@@ -30,8 +30,10 @@ database_option: {
   | WAL_LEVEL {1 | 2}
   | VGROUPS value
   | SINGLE_STABLE {0 | 1}
+  | STT_TRIGGER value
   | TABLE_PREFIX value
   | TABLE_SUFFIX value
+  | TSDB_PAGESIZE value
   | WAL_RETENTION_PERIOD value
   | WAL_ROLL_PERIOD value
   | WAL_RETENTION_SIZE value
@@ -69,8 +71,10 @@ database_option: {
 - SINGLE_STABLE：表示此数据库中是否只可以创建一个超级表，用于超级表列非常多的情况。
   - 0：表示可以创建多张超级表。
   - 1：表示只可以创建一张超级表。
+- STT_TRIGGER：表示落盘文件触发文件合并的个数。默认为 8，范围 1 到 16。
 - TABLE_PREFIX：内部存储引擎根据表名分配存储该表数据的 VNODE 时要忽略的前缀的长度。
 - TABLE_SUFFIX：内部存储引擎根据表名分配存储该表数据的 VNODE 时要忽略的后缀的长度。
+- TSDB_PAGESIZE：一个 VNODE 中时序数据存储引擎的页大小，单位为 KB，默认为 4 KB。范围为 1 到 16384，即 1 KB到 16 MB。
 - WAL_RETENTION_PERIOD：wal 文件的额外保留策略，用于数据订阅。wal 的保存时长，单位为 s。单副本默认为 0，即落盘后立即删除。-1 表示不删除。多副本默认为 4 天。
 - WAL_RETENTION_SIZE：wal 文件的额外保留策略，用于数据订阅。wal 的保存的最大上限，单位为 KB。单副本默认为 0，即落盘后立即删除。多副本默认为-1，表示不删除。
 - WAL_ROLL_PERIOD：wal 文件切换时长，单位为 s。当 wal 文件创建并写入后，经过该时间，会自动创建一个新的 wal 文件。单副本默认为 0，即仅在落盘时创建新文件。多副本默认为 1 天。

docs/zh/12-taos-sql/06-select.md

@@ -350,9 +350,9 @@ SELECT AVG(CASE WHEN voltage < 200 or voltage > 250 THEN 220 ELSE voltage END) F
 
 ## JOIN 子句
 
-TDengine 支持“普通表与普通表之间”、“超级表与超级表之间”、“子查询与子查询之间” 进行自然连接。自然连接与内连接的主要区别是，自然连接要求参与连接的字段在不同的表/超级表中必须是同名字段。也即，TDengine 在连接关系的表达中，要求必须使用同名数据列/标签列的相等关系。
+TDengine 支持基于时间戳主键的内连接，即 JOIN 条件必须包含时间戳主键。只要满足基于时间戳主键这个要求，普通表、子表、超级表和子查询之间可以随意的进行内连接，且对表个数没有限制。
 
-在普通表与普通表之间的 JOIN 操作中，只能使用主键时间戳之间的相等关系。例如：
+普通表与普通表之间的 JOIN 操作：
 
 ```sql
 SELECT *
@@ -360,7 +360,7 @@ FROM temp_tb_1 t1, pressure_tb_1 t2
 WHERE t1.ts = t2.ts
 ```
 
-在超级表与超级表之间的 JOIN 操作中，除了主键时间戳一致的条件外，还要求引入能实现一一对应的标签列的相等关系。例如：
+超级表与超级表之间的 JOIN 操作：
 
 ```sql
 SELECT *
@@ -368,20 +368,15 @@ FROM temp_stable t1, temp_stable t2
 WHERE t1.ts = t2.ts AND t1.deviceid = t2.deviceid AND t1.status=0;
 ```
 
-类似地，也可以对多个子查询的查询结果进行 JOIN 操作。
-
-:::note
-
-JOIN 语句存在如下限制要求：
+子表与超级表之间的 JOIN 操作：
 
-- 参与一条语句中 JOIN 操作的表/超级表最多可以有 10 个。
-- 在包含 JOIN 操作的查询语句中不支持 FILL。
-- 暂不支持参与 JOIN 操作的表之间聚合后的四则运算。
-- 不支持只对其中一部分表做 GROUP BY。
-- JOIN 查询的不同表的过滤条件之间不能为 OR。
-- JOIN 查询要求连接条件不能是普通列，只能针对标签和主时间字段列（第一列）。
+```sql
+SELECT *
+FROM temp_ctable t1, temp_stable t2
+WHERE t1.ts = t2.ts AND t1.deviceid = t2.deviceid AND t1.status=0;
+```
 
-:::
+类似地，也可以对多个子查询的查询结果进行 JOIN 操作。
 
 ## 嵌套查询