Serach Column in Existing table in Database and alter table

/*ADD one column "ColumnName" in table TableName */
 
 IF NOT EXISTS  ( SELECT 'X' FROM INFORMATION_SCHEMA.COLUMNS COLUMNS, INFORMATION_SCHEMA.TABLES TABLES

WHERE
COLUMNS.TABLE_NAME=TABLES.TABLE_NAME AND UPPER(COLUMNS.COLUMN_NAME)=UPPER('ColumnName') AND UPPER(TABLES.TABLE_NAME) = UPPER('TableName'))

BEGIN

ALTER TABLE  TableName    ADD ColumnName   INT Default(0)

END

GO