想要快速檢查數據字段

Question

我們有一個由兩部分組成的數據庫設置：靜態結構和動態添加。對於每個數據庫，動態可能不同，有時我們沒有所有動態字段的數據。 Rigt現在，我們通過查看整個表中的記錄總數來檢查容器，但是如果可能的話，我們希望轉移到更精確的檢查容器的方法。是否有可能通過幾百個字段快速查看哪些字段是空的，哪些字段是填充的？

Answer 1

用於搜索在任一列NULLS你可以做到這一點任何行，首先要創建這個PROC是基於這裏的代碼Search all columns in all the tables in a database for a specific value

CREATE PROCEDURE FindMyData_StringNull 
    @DataToFind NVARCHAR(4000), 
    @ExactMatch BIT = 0 
AS 
SET NOCOUNT ON 

DECLARE @Temp TABLE(RowId INT IDENTITY(1,1), SchemaName sysname, TableName sysname, ColumnName SysName, DataType VARCHAR(100), DataFound BIT) 

    INSERT INTO @Temp(TableName,SchemaName, ColumnName, DataType) 
    SELECT C.Table_Name,C.TABLE_SCHEMA, C.Column_Name, C.Data_Type 
    FROM Information_Schema.Columns AS C 
      INNER Join Information_Schema.Tables AS T 
       ON C.Table_Name = T.Table_Name 
     AND C.TABLE_SCHEMA = T.TABLE_SCHEMA 
    WHERE Table_Type = 'Base Table' 



DECLARE @i INT 
DECLARE @MAX INT 
DECLARE @TableName sysname 
DECLARE @ColumnName sysname 
DECLARE @SchemaName sysname 
DECLARE @SQL NVARCHAR(4000) 
DECLARE @PARAMETERS NVARCHAR(4000) 
DECLARE @DataExists BIT 
DECLARE @SQLTemplate NVARCHAR(4000) 

SELECT @SQLTemplate = 'If Exists(Select * 
              From ReplaceTableName 
              Where Convert(nVarChar(4000), [ReplaceColumnName]) 
                 IS NULL 
             ) 
            Set @DataExists = 1 
           Else 
            Set @DataExists = 0' 
          , 
     @PARAMETERS = '@DataExists Bit OUTPUT', 
     @i = 1 

SELECT @i = 1, @MAX = MAX(RowId) 
FROM @Temp 

WHILE @i <= @MAX 
    BEGIN 
     SELECT @SQL = REPLACE(REPLACE(@SQLTemplate, 'ReplaceTableName', QUOTENAME(SchemaName) + '.' + QUOTENAME(TableName)), 'ReplaceColumnName', ColumnName) 
     FROM @Temp 
     WHERE RowId = @i 


     PRINT @SQL 
     EXEC SP_EXECUTESQL @SQL, @PARAMETERS, @DataExists = @DataExists OUTPUT 

     IF @DataExists =1 
      UPDATE @Temp SET DataFound = 1 WHERE RowId = @i 

     SET @i = @i + 1 
    END 

SELECT SchemaName,TableName, ColumnName 
FROM @Temp 
WHERE DataFound = 1 

這樣稱呼它

FindMyData_StringNull NULL,1 

Answer 2

假設您只是檢查列中是否存在非NULL值，使用EXISTS通常應比獲取COUNT（*）快。 COUNT需要掃描整個表格以獲得正確的數字。 EXISTS只需要在停止查找之前找到滿足條件的一行。

如果整列爲NULL，那麼時間將大致相同，但在所有這些情況下，如果您有值，則可能會大大縮短。

Answer 3

從Search all columns in all the tables in a database for a specific value

先創建這個功能

CREATE PROCEDURE FindMyData_String 
    @DataToFind NVARCHAR(4000), 
    @ExactMatch BIT = 0 
AS 
SET NOCOUNT ON 

DECLARE @Temp TABLE(RowId INT IDENTITY(1,1), SchemaName sysname, TableName sysname, ColumnName SysName, DataType VARCHAR(100), DataFound BIT) 

    INSERT INTO @Temp(TableName,SchemaName, ColumnName, DataType) 
    SELECT C.Table_Name,C.TABLE_SCHEMA, C.Column_Name, C.Data_Type 
    FROM Information_Schema.Columns AS C 
      INNER Join Information_Schema.Tables AS T 
       ON C.Table_Name = T.Table_Name 
     AND C.TABLE_SCHEMA = T.TABLE_SCHEMA 
    WHERE Table_Type = 'Base Table' 
      And Data_Type In ('ntext','text','nvarchar','nchar','varchar','char') 


DECLARE @i INT 
DECLARE @MAX INT 
DECLARE @TableName sysname 
DECLARE @ColumnName sysname 
DECLARE @SchemaName sysname 
DECLARE @SQL NVARCHAR(4000) 
DECLARE @PARAMETERS NVARCHAR(4000) 
DECLARE @DataExists BIT 
DECLARE @SQLTemplate NVARCHAR(4000) 

SELECT @SQLTemplate = CASE WHEN @ExactMatch = 1 
          THEN 'If Exists(Select * 
              From ReplaceTableName 
              Where Convert(nVarChar(4000), [ReplaceColumnName]) 
                 = ''' + @DataToFind + ''' 
             ) 
            Set @DataExists = 1 
           Else 
            Set @DataExists = 0' 
          ELSE 'If Exists(Select * 
              From ReplaceTableName 
              Where Convert(nVarChar(4000), [ReplaceColumnName]) 
                 Like ''%' + @DataToFind + '%'' 
             ) 
            Set @DataExists = 1 
           Else 
            Set @DataExists = 0' 
          END, 
     @PARAMETERS = '@DataExists Bit OUTPUT', 
     @i = 1 

SELECT @i = 1, @MAX = MAX(RowId) 
FROM @Temp 

WHILE @i <= @MAX 
    BEGIN 
     SELECT @SQL = REPLACE(REPLACE(@SQLTemplate, 'ReplaceTableName', QUOTENAME(SchemaName) + '.' + QUOTENAME(TableName)), 'ReplaceColumnName', ColumnName) 
     FROM @Temp 
     WHERE RowId = @i 


     PRINT @SQL 
     EXEC SP_EXECUTESQL @SQL, @PARAMETERS, @DataExists = @DataExists OUTPUT 

     IF @DataExists =1 
      UPDATE @Temp SET DataFound = 1 WHERE RowId = @i 

     SET @i = @i + 1 
    END 

SELECT SchemaName,TableName, ColumnName 
FROM @Temp 
WHERE DataFound = 1 

現在，在任何字符串類型的列稱呼它爲空字符串行

exec FindMyData_String '',1 

它會給你的輸出列名，表名和模式名稱 請記住，它將搜索所有表

Answer 4

我認爲最簡單的解決方案是使用CHECKSUM功能。首先，您需要確定空行上的校驗和，然後將其與其他行進行比較。

Select Checksum(*) 
From Table 

在這裏使用*的漁獲是它將包括PK。您可能必須指定除PK之外的各個列以獲得準確的讀數。因此，像：

Select Checksum(Col1, Col2, Col3) 
From Table 

Checksum Function.