How to use SQL commands to modify a non-null (notnull) field in a data table _ PHP Tutorial

Use SQL commands to modify a non-null (notnull) statement in a data table. ALTERTABLEtable1ALTERCOLUMN [name] varchar (60) NULL; why [] is added to the name field of Table 1, because name is an SQL keyword conflict and an error occurs, just in case. If

Alter table table1 alter column [name] varchar (60) NULL;

Table 1 table name
Why [] is added to the name field name, because name is an SQL keyword conflict and an error occurs, just in case.

If the name field has already created an index, if you need to modify it, you must first delete the index before it can be correctly performed.

Http://www.bkjia.com/PHPjc/322002.htmlwww.bkjia.comtruehttp://www.bkjia.com/PHPjc/322002.htmlTechArticleALTER TABLE table1 alter column [name] varchar (60) NULL; why [] is added to the table1 TABLE name field name, because name is an SQL keyword that will conflict with the error, so that it is in case. If...