SQL 查询中使用的表列表

Question

有没有办法获取 SQL 查询中使用的表的列表？ 例子 ： 我有类似的东西：

SELECT * FROM Table t JOIN OtherTable ON t.id=OtherTable.t_id

我希望得到

Table, OtherTable

谢谢

Answer 1

使用 C# 的一个解决方案是导入 Microsoft.SqlServer.TransactSql.ScriptDom（我在 C:\Program Files (x86)\Microsoft SQL Server\120\SDK\Assemblies\Microsoft.SqlServer.TransactSql.ScriptDom.dll 找到了 dll）然后执行以下操作：

private List<string> GetTableNamesFromQueryString(string query)
{
    IList<ParseError> errors = new List<ParseError>();
    IList<TSqlParserToken> queryTokens;
    List<string> output = new List<string>(16);
    StringBuilder sb = new StringBuilder(128);
    TSql120Parser parser = new TSql120Parser(true);
    TSqlTokenType[] fromTokenTypes = new TSqlTokenType[2]
        {
            TSqlTokenType.From,
            TSqlTokenType.Join
        };
    TSqlTokenType[] identifierTokenTypes = new TSqlTokenType[2]
        {
            TSqlTokenType.Identifier,
            TSqlTokenType.QuotedIdentifier
        };

    using (System.IO.TextReader tReader = new System.IO.StringReader(query))
    {
        queryTokens = parser.GetTokenStream(tReader, out errors);
        if (errors.Count > 0) { return errors.Select(e=>"Error: " + e.Number + " Line: " + e.Line + " Column: " + e.Column + " Offset: " + e.Offset + " Message: " + e.Message).ToList(); }

        for (int i = 0; i < queryTokens.Count; i++)
        {
            if(fromTokenTypes.Contains(queryTokens[i].TokenType))
            {
                for (int j = i + 1; j < queryTokens.Count; j++)
                {
                    if (queryTokens[j].TokenType == TSqlTokenType.WhiteSpace) { continue; }
                    else if (identifierTokenTypes.Contains(queryTokens[j].TokenType))
                    {
                        sb.Clear();

                        GetQuotedIdentifier(queryTokens[j], sb);            //Change Identifiers to QuotedIdentifier (text only)

                        while (j + 2 < queryTokens.Count && queryTokens[j + 1].TokenType == TSqlTokenType.Dot && identifierTokenTypes.Contains(queryTokens[j + 2].TokenType))
                        {
                            sb.Append(queryTokens[j + 1].Text);
                            GetQuotedIdentifier(queryTokens[j + 2], sb);    //Change Identifiers to QuotedIdentifier (text only)

                            j += 2;
                        }

                        output.Add(sb.ToString());
                        break;              //exit the loop
                    }
                    else { break; }             //exit the loop if token is not a FROM, a JOIN, or white space.
                }

            }
        }

        return output.Distinct().OrderBy(tableName => tableName).ToList();
    }
}

private void GetQuotedIdentifier(TSqlParserToken token, StringBuilder sb)
{
    switch(token.TokenType)
    {
        case TSqlTokenType.Identifier: sb.Append('[').Append(token.Text).Append(']'); return;
        case TSqlTokenType.QuotedIdentifier: sb.Append(token.Text); return;
        default: throw new ArgumentException("Error: expected TokenType of token should be TSqlTokenType.Identifier or TSqlTokenType.QuotedIdentifier");
    }
}

我在尝试让this answer 工作后想出了这个。

Answer 2

您可以在查询后立即使用此 sql 脚本。它将返回上次执行的查询中使用的表列表：

   SELECT Field1, Field2 
   FROM Table t JOIN OtherTable ON t.id=OtherTable.t_id

  ;WITH vwQueryStats AS(
     SELECT 
      COALESCE(OBJECT_NAME(s2.objectid),'Ad-Hoc') AS ProcName
      ,execution_count
      ,s2.objectid
      ,(
         SELECT TOP 1 
            SUBSTRING(s2.TEXT,statement_start_offset / 2+1 
            ,( ( CASE WHEN statement_end_offset = -1
                THEN (LEN(CONVERT(NVARCHAR(MAX),s2.TEXT)) * 2)
                ELSE statement_end_offset END)- statement_start_offset) / 2+1)) AS sql_statement
            ,last_execution_time
         FROM sys.dm_exec_query_stats AS s1
         CROSS APPLY sys.dm_exec_sql_text(sql_handle) AS s2
    )
    SELECT TOP 1 * 
    INTO #lastQueryStats
    FROM vwQueryStats x
    WHERE sql_statement NOT like 'WITH vwQueryStats AS%'
    ORDER BY last_execution_time DESC

    SELECT
    TABLE_NAME
    FROM #lastQueryStats, INFORMATION_SCHEMA.TABLES tab 
    WHERE CHARINDEX( tab.TABLE_NAME, sql_statement) > 0


    DROP TABLE #lastQueryStats 

我使用了从这个post 中检索最后执行的查询的查询，并对其进行了一些修改以与您的示例相匹配。

输出将按照您的要求：

 Table
 OtherTable

如果你想让它们用逗号分隔，你可以这样做：

DECLARE @tableNames VARCHAR(MAX) 

SELECT @tableNames = COALESCE(@tableNames + ', ', '') + TABLE_NAME
FROM   #lastQueryStats, INFORMATION_SCHEMA.TABLES tab 
WHERE  CHARINDEX( tab.TABLE_NAME, sql_statement) > 0

SELECT @tableNames 

但是，您应该注意，在同时执行数千个查询的“常规”生产或 QA 环境中，这可能不起作用，因为在您的第一个查询和从数据库统计信息中提取信息的查询之间可能会执行另一个查询。

希望对你有帮助

Answer 3

以下代码基于 Trisped 的回答，但经过修改以使用省略架构名称的完全限定表名，以及一些清理/优化：

public class Parser
{
    public static List<string> GetTableNamesFromQueryString(string query)
    {
        var output = new List<string>();
        var sb = new StringBuilder();
        var parser = new TSql120Parser(true);

        var fromTokenTypes = new[]
        {
            TSqlTokenType.From,
            TSqlTokenType.Join
        };

        var identifierTokenTypes = new[]
        {
            TSqlTokenType.Identifier,
            TSqlTokenType.QuotedIdentifier
        };

        using (System.IO.TextReader tReader = new System.IO.StringReader(query))
        {
            IList<ParseError> errors;
            var queryTokens = parser.GetTokenStream(tReader, out errors);
            if (errors.Any())
            {
                return errors
                    .Select(e => string.Format("Error: {0}; Line: {1}; Column: {2}; Offset: {3};  Message: {4};", e.Number, e.Line, e.Column, e.Offset, e.Message))
                    .ToList();
            }

            for (var i = 0; i < queryTokens.Count; i++)
            {
                if (fromTokenTypes.Contains(queryTokens[i].TokenType))
                {
                    for (var j = i + 1; j < queryTokens.Count; j++)
                    {
                        if (queryTokens[j].TokenType == TSqlTokenType.WhiteSpace)
                        {
                            continue;
                        }

                        if (identifierTokenTypes.Contains(queryTokens[j].TokenType))
                        {
                            sb.Clear();
                            GetQuotedIdentifier(queryTokens[j], sb);

                            while (j + 2 < queryTokens.Count 
                                && queryTokens[j + 1].TokenType == TSqlTokenType.Dot 
                                && (queryTokens[j + 2].TokenType == TSqlTokenType.Dot || identifierTokenTypes.Contains(queryTokens[j + 2].TokenType)))
                            {
                                sb.Append(queryTokens[j + 1].Text);

                                if (queryTokens[j + 2].TokenType == TSqlTokenType.Dot)
                                {
                                    if (queryTokens[j - 1].TokenType == TSqlTokenType.Dot) 
                                        GetQuotedIdentifier(queryTokens[j + 1], sb);

                                    j++;

                                }
                                else
                                {
                                    GetQuotedIdentifier(queryTokens[j + 2], sb);
                                    j += 2;
                                }
                            }

                            output.Add(sb.ToString());
                        }
                        break;
                    }
                }
            }

            return output.Distinct().OrderBy(tableName => tableName).ToList();
        }
    }

    private static void GetQuotedIdentifier(TSqlParserToken token, StringBuilder sb)
    {
        switch (token.TokenType)
        {
            case TSqlTokenType.Identifier: 
                sb.Append('[').Append(token.Text).Append(']'); 
                break;
            case TSqlTokenType.QuotedIdentifier:
            case TSqlTokenType.Dot: 
                sb.Append(token.Text); 
                break;

            default: throw new ArgumentException("Error: expected TokenType of token should be TSqlTokenType.Dot, TSqlTokenType.Identifier, or TSqlTokenType.QuotedIdentifier");
        }
    }
}

Answer 4

实现此目的的一种hackish方法是显式命名查询中的字段并在它们前面加上表名，例如

SELECT Field1 As "OtherTable.Field1",
       Field2 As "Table.Field2"
FROM Table t JOIN OtherTable ON t.id=OtherTable.t_id

本质上，您是在查询结果中提供自己的元数据。查询返回后，查看列名并实现自定义逻辑来拆分表名。

Answer 5

Trisped 的解决方案完美运行。我修改了一行以确保不区分大小写并去掉括号。

旧：output.Add(sb.ToString());

新：output.Add(sb.ToString().ToLower().Trim(new char[]{'[', ']'}));