Question

我正在尝试修改以下查询以返回特定表中的所有列的列表（不是现在的DB中的所有表），其中字段为null或为空。

据我所知，需要将游标声明更改为指定搜索表，但需要进行其他更改才能返回空列的名称。

帮助将受到高度赞赏。

declare @tempTable TABLE
(
    TableSchema nvarchar(256),
    TableName nvarchar(256),
    ColumnName sysname,
    NotNullCnt bigint
);

declare @sql nvarchar(4000);
declare @tableSchema nvarchar(256);
declare @tableName nvarchar(256);
declare @columnName sysname;
declare @cnt bigint;

declare columnCursor cursor FOR
    SELECT TABLE_SCHEMA, TABLE_NAME, COLUMN_NAME FROM INFORMATION_SCHEMA.COLUMNS
    WHERE IS_NULLABLE = 'YES';

open columnCursor;

fetch next FROM columnCursor INTO @tableSchema, @tableName, @columnName;

while @@FETCH_STATUS = 0
begin

    SET @sql = 'select @cnt = COUNT(*) from [' + @tableSchema + '].[' + @tableName +
        '] where [' + @columnName + '] is not null';

    exec sp_executesql @sql, N'@cnt bigint output', @cnt = @cnt output;

    INSERT INTO @tempTable SELECT @tableSchema, @tableName, @columnName, @cnt;

    fetch next FROM columnCursor INTO @tableSchema, @tableName, @columnName;
end

close columnCursor;
deallocate columnCursor;

SELECT * FROM @tempTable WHERE NotNullCnt = 0;

返回列的值为null或所有记录为空的特定表中的所有列的列表

0 个答案: