How Can I Parse Transact-SQL Code in C#?

Parsing SQL Code in C#

When working with SQL code in C#, the need arises to parse and analyze its structure. One approach is to leverage existing parsers that can generate structured representations of the code.

Specific SQL Parser

Specifically for Transact-SQL (Microsoft SQL Server), the Microsoft.SqlServer.Management.SqlParser.Parser namespace provides an effective means of parsing SQL code. This namespace is part of the Microsoft.SqlServer.Management.SqlParser.dll assembly, which is included with SQL Server and can be freely distributed.

Parsing Example

To parse T-SQL code as a string into a sequence of tokens, the following method can be employed:

IEnumerable<TokenInfo> ParseSql(string sql)
{
    ParseOptions parseOptions = new ParseOptions();
    Scanner scanner = new Scanner(parseOptions);

    int state = 0,
        start,
        end,
        lastTokenEnd = -1,
        token;

    bool isPairMatch, isExecAutoParamHelp;

    List<TokenInfo> tokens = new List<TokenInfo>();

    scanner.SetSource(sql, 0);

    while ((token = scanner.GetNext(ref state, out start, out end, out isPairMatch, out isExecAutoParamHelp)) != (int)Tokens.EOF)
    {
        TokenInfo tokenInfo =
            new TokenInfo()
            {
                Start = start,
                End = end,
                IsPairMatch = isPairMatch,
                IsExecAutoParamHelp = isExecAutoParamHelp,
                Sql = sql.Substring(start, end - start + 1),
                Token = (Tokens)token,
            };

        tokens.Add(tokenInfo);

        lastTokenEnd = end;
    }

    return tokens;
}

Additional Considerations

Note that the TokenInfo class is a simple class encapsulating the relevant properties. The Tokens enumeration contains constants representing various token types, such as TOKEN_BEGIN, TOKEN_COMMIT, and TOKEN_EXISTS.

Recently, the Microsoft.SqlServer.Management.SqlParser namespace has been made available as a separate NuGet package, making it convenient to integrate into C# projects: https://www.nuget.org/packages/Microsoft.SqlServer.Management.SqlParser

The above is the detailed content of How Can I Parse Transact-SQL Code in C#?. For more information, please follow other related articles on the PHP Chinese website!