-- By default, for backward compatibility a settings profile constraint for a specific setting inherit every not set field from previous profile. You can change this behaviour by setting this to true. If it's set to true then if settings profile has a constraint for a specific setting, then...
= '1' and fk_category_id = #{typeId} order by sort select <include refid="Base_Column_List"/> from sys_data_dictionary where del_flag='0' and type=#{type} and value=#{value} select <include refid="Base_Column_List"/> from sys_data_dictionary where del_flag='0' and type...
{ 'date': 'Date', 'code': 'String', 'name': 'String', 'open': 'Float32', 'high': 'Float32', 'low': 'Float32', 'close': 'Float32', 'change': 'Float32', 'change_amount': 'Float32', 'volume': 'Float64', 'amount': 'Float64', 'amplitude': 'Float32', 'turnover':...
不支持 CTE(Common Table Expression),仅使用一个 String 来作为 column 的标识(DataSchema),使用类似 Monad 的 Nullable(T) 表示 NULL 的类型却不允许嵌套的 Nullable,没有 Join reorder 优化,分布式查询仅支持简单的 Broadcast Join 和 Aggregate,不支持事务也没有任何并发控制机制。
┌─Column Name───┬─Column Type─┬─compressed─┬─uncompressed─┬─Compression Ratio─┬─compression_codec─┐ │ changeable │ UInt8 │ 188.32 KiB │ 41.27 MiB │ 224.41 │ │ │ averageSignal │ UInt8 │ 188.32 KiB │ 41.27 MiB │ 224.41 │ │ ...
Change the data type of a column if data type conversion is supported. Delete a nullable column. Create or modify a column in the distributed table. Create or modify a column in the local table. Create a non-nullable column. Stop writing data. ...
Allow HedgedConnections to change replica until receiving first data packet--queue_max_wait_ms arg The wait timeinthe request queue,ifthe numberofconcurrent requests exceeds the maximum.--connection_pool_max_wait_ms arg The wait time when the connection pool ...
ClickHouse are implemented more like insert triggers. If there’s some aggregation in the view >query, it’s applied only to the batch of freshly inserted data. Any changes to existing data of source table (like update, >delete, drop partition, etc.) does not change the materialized view....
Fix bug for ReplicatedMerge table engines when ALTER MODIFY COLUMN query doesn't change the type of Decimal column if its size (32 bit or 64 bit) doesn't change. #21728 (alesapin). Fix possible infinite waiting when concurrent OPTIMIZE and DROP are run for ReplicatedMergeTree. #21716 (Az...
ALTER TABLE visits COMMENT COLUMN browser 'The table shows the browser used for accessing the site.' 1. 修改列 MODIFY COLUMN [IF EXISTS] name [type] [default_expr] [TTL] 1. 该语句可以改变 name Type Default expression TTL 有关修改列TTL的示例,请参见Column TTL. ...