tableColumnAction ::= { ADD [ COLUMN ] [ IF NOT EXISTS ] <col_name> <col_type> [ { DEFAULT <default_value> | { AUTOINCREMENT | IDENTITY } /* AUTOINCREMENT (or IDENTITY) is supported only for */ /* columns with numeric data types (NUMBER, INT, FLOAT, etc.). */ /* Also, ...
-- single columnALTERTABLEempl_infomodifycolumnempl_idunsetmasking policy;-- multiple columnsALTERTABLEempl_infoMODIFYCOLUMNempl_idUNSETMASKING POLICY,COLUMNempl_dobUNSETMASKING POLICY;
系统函数: system$clustering_depth: 返回表平均的ClusteringDepth,可以指定columns参数 system$clustering_information: 返回表相关clustering 信息,包含average_overlaps,average_depth,partition_depth_histogram等 锁优化 Selection 和 Merge 进行不会对原始数据持有锁,也就是说在这两个过程中都不会卡主用户数据的查询和插...
Adding columns or altering table structures can be accomplished with theALTER TABLEcommand: SQL ALTER TABLE my_database.my_schema.my_table ADD COLUMN email STRING; Removing Tables To drop a table, use the commandDROP TABLE: SQL DROP TABLE my_database.my_schema.my_table; 6. Data Loading and...
alter table table1 add column col3 varchar not null constraint uniq_col3 unique not enforced; The following example will create a parent table with a Snowflake Primary Key constraint and another table with a foreign key constraint that points to the same columns as the first table’s primary...
Views including the columns Stored procedures including the parameter dataset and result set Functions including the parameter dataset Pipes Stages Streams including the columns Tasks Sequences Fetching static lineage on assets relationships among tables, views, streams, and stored procedures. ...
For Snowflake integration, it is important that the selected fields exactly match the number of columns and their names of the table defined in Snowflake, so avoid adding extra fields or selecting from *. Add an action, select Snowflake from the Action Type dropdown list, keep the action ...
data type (one of Snowflake data types); you can also use the select box in the table header to bulk set the type for all columns. Setting the data type to IGNORE means that column will not be present in the destination table. nullable; when checked, the column will be marked as nul...
Key columns For updates, upserts and deletes, a key column or columns must be set to determine which row to alter. No Array keys Table action Determines whether to recreate or remove all rows from the destination table prior to writing.- None: No action will be done to the table.- Rec...
SELECT Specific Columns in a Table Commas in the Front or Back? Place your Commas in front for better Debugging Capabilities Sort the Data with the ORDER BY Keyword Use a Column Name or Number in an ORDER BY Statement Two Examples of ORDER BY using Different Techniques ...