altertablemyTableaddmyNewColumnintnull; while1=1beginupdatetop (100000) myTablesetmyNewColumn=myOldColumnwheremyNewColumnisnull; if @@ROWCOUNT=0break;endaltertablemyTabledropcolumnmyOldColumn;EXECsp_RENAME'[myTable].[myNewColumn]','myOldColumn','COLUMN'
CHANGE COLUMN命令的语法格式如下: ALTERTABLEtable_name CHANGECOLUMNold_column_name new_column_name new_data_type; 1. 2. 其中,table_name是要修改的表名,old_column_name是要修改的列名,new_column_name是修改后的列名,new_data_type是修改后的数据类型。 实例演示 现有一个名为users的表,包含id、name和...
syntaxsqlCopy CHANGETABLE( {CHANGES<table_name>,<last_sync_version>|VERSION<table_name>,<primary_key_values>} , [FORCESEEK] ) [AS]<table_alias>[ (<column_alias>[ ,...n ] )<primary_key_values>::=(<column_name>[ , ...n ] ) , (<value>[ , ...n ] ) ...
Now I want to change the column data type in target table sql server database from VARCHAR to DATETIME with out interrupting the data.I dont want to drop or delete the table as there is huge data residing in the tables.Please advice.Thanks in Advance,Sam.All replies (6)Friday, Febru...
syntaxsql複製 CHANGETABLE( {CHANGES<table_name>,<last_sync_version>|VERSION<table_name>,<primary_key_values>} , [FORCESEEK] ) [AS]<table_alias>[ (<column_alias>[ ,...n ] )<primary_key_values>::=(<column_name>[ , ...n ] ) , (<value>[ , ...n ] ) ...
syntaxsql复制 CHANGETABLE( {CHANGES<table_name>,<last_sync_version>|VERSION<table_name>,<primary_key_values>} , [FORCESEEK] ) [AS]<table_alias>[ (<column_alias>[ ,...n ] )<primary_key_values>::=(<column_name>[ , ...n ] ) , (<value>[ , ...n ] ) ...
Transact-SQL Syntax Conventions Syntax CHANGETABLE ( { CHANGES table , last_sync_version | VERSION table , <primary_key_values> } ) [AS] table_alias [ ( column_alias [ ,...n ] ) <primary_key_values> ::= ( column_name [ , ...n ] ) , ( value [ , ...n ] ) ...
语法结构相对简单，基本格式为ALTERTABLE table_name MODIFY column_name new_data_type[constraints];。例如，假设有一个名为employees的表，其中包含列salary数据类型为INT，现在需要将其改为DECIMAL(10,2)以支持小数点数值。使用MODIFY命令的SQL语句为ALTERTABLE employees MODIFY salaryDECIMAL(10,2);。执行此命令后...
下面是Hive中ALTER COLUMN语法的基本形式: ALTERTABLEtable_name CHANGECOLUMNold_column_name new_column_name column_type[COMMENTcolumn_comment][FIRST|AFTERcolumn_name]; 1. 上述语法中,我们需要提供以下信息: table_name:要修改的表的名称。 old_column_name:要更改的现有列的名称。
object_id int ID of the change table. Is unique within a database. version int Identified for informational purposes only. Not supported. Future compatibility is not guaranteed. For SQL Server 2012 (11.x), this column always returns 0. source_object_id int ID of the source table enabled ...