RegEx to parse stored procedure and object names from DDL in a .sql file C#

问题

I have a .sql file which may contain DDL definitions of several stored procedures, alter statements for Tables, Triggers, Views etc

It could have statements like these :

CREATE PROC / CREATE PROCEDURE
ALTER PROC / ALTER PROCEDURE
DROP PROC / DROP PROCEDURE
CREATE TABLE/TRIGGER/VIEW
ALTER TABLE/TRIGGER/VIEW
DROP TABLE/TRIGGER/VIEW
etc

What is the best way to parse the .sql file and just get the list of objects(Proc/Table/View names) and the action that is being taken on them (ALTER/CREATE/DROP)? I am thinking instead of using stuff like Microsoft.Data.Schema.ScriptDom or ANTLR or other parsers, the easiest way is to use a RegEx. But not sure what kind of RegEx should I write which covers all the scenarios.

So far, this expression is able to match all the above rules. But how do I get the name of the object in front of it. eg. it matches

(create|alter|drop)\s+(procedure|proc|table|trigger|view|function|constraint)

How do I get the name AdvisorGroups is my question. My RegEx is also imperfect because it could have [dbo]. in front of it or not. It could just be Alter table AdvisorGroups too. I am not trying to take care of all possibilites. Just the bare minimum.

ALTER TABLE [dbo].[AdvisorGroups] ADD CONSTRAINT [XXX]

-Thanks in advance

回答1:

RegEx won't get the job done - definitely... you will need a real parser - like this one (commercial).

回答2:

I worked it out myself. Hope it helps someone. So for a string containing a jumble of ALTER, DROP, CREATE PROC/TABLE/TRIGGER/FUNCTION

    Regex DDL = new Regex(@"(?<=\b(create|alter|drop)\s+(procedure|proc|table|trigger|view|function)\b\s\[dbo\].)\[.*?\]", RegexOptions.IgnoreCase);
    Match match = DDL.Match(inputScript);
    while(match.Success)
    {
        textBox2.Text += "\r\n" + match.Groups[1].Value + " - " + match.Groups[2].Value + " - " +  match.Value;
        match = match.NextMatch();
    }
    textBox3.Text = "DONE";

You will get output like this.

CREATE - VIEW - vwEmployees
CREATE - TABLE - tblSalaries
DROP - PROC - spGetEmployees
ALTER - TABLE - tblSalaries

The awesomeness of this code is that, not only does it give you the object being affected but it even gives you the kind of object (i.e table, proc, view) and what operation (eg. create/alter/drop). All these are available in matches[1], matches[2] etc.

来源：https://stackoverflow.com/questions/14903705/regex-to-parse-stored-procedure-and-object-names-from-ddl-in-a-sql-file-c-sharp

标签

regex

parsing

sql-parser

tsql-parser