sp_grantdbaccess (Transact-SQL MetaData) Definition

Please note: that the following source code is provided and copyrighted by Microsoft and is for educational purpose only.
The meta data is from an SQL 2012 Server.

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Definition:

sys.sp_grantdbaccess(nvarchar @loginame)

MetaData:

 create procedure sys.sp_grantdbaccess  
    @loginame       sysname,  
    @name_in_db     sysname = NULL OUT  
as  
    --  SETUP RUNTIME OPTIONS / DECLARE VARIABLES --   
    set nocount on  
    declare @ret        int,    --  return value of sp call  
            @sid        varbinary(85),  
            @iswin        bit,  
            @isgrp        bit,  
            @stmtU        nvarchar(4000),  
            @stmtS        nvarchar(4000)  
              
    if @name_in_db is null  
        select @name_in_db = @loginame  
  
    --  CHECK PERMISSIONS (Shiloh Check) --   
    if (not is_member('db_accessadmin') = 1) and  
           (not is_member('db_owner') = 1)  
    begin  
        dbcc auditevent (109, 1, 0, @loginame, @name_in_db, NULL, NULL, NULL, NULL, NULL)  
        raiserror(15247,-1,-1)  
        return (1)  
    end  
  
    --  DISALLOW USER TRANSACTION --   
    set implicit_transactions off  
    IF (@@trancount > 0)  
    begin  
        raiserror(15002,-1,-1,'sys.sp_grantdbaccess')  
        return (1)  
    end  
  
    exec @ret = sys.sp_validname @name_in_db  
    if @ret <> 0  
        return(1)  
  
    --  IS IT A WINDOWS ACCOUNT?  
    select @iswin = case when (charindex('\', @loginame) <> 0) then 1 else 0 end  
    select @isgrp = 0  
  
    --  IS IT A WINDOWS GROUP?  
    if @iswin = 1  
    begin  
        select @sid = get_sid('\G'+@loginame)     --  nt group?  
        if @sid is not null  
            select @isgrp = 1    --  nt group  
    end  
  
    --  Form Create User statement  
    select @stmtU = 'CREATE USER '  
    select @stmtU = @stmtU + quotename(@name_in_db, ']')  
    select @stmtU = @stmtU + ' FOR LOGIN '  
    select @stmtU = @stmtU + quotename(@loginame, ']')  
    if @isgrp = 0  
    begin  
        select @stmtU = @stmtU + ' WITH DEFAULT_SCHEMA = '  
        select @stmtU = @stmtU + quotename(@name_in_db, ']')  
    end  
  
    --  Form Create Schema statement  
    select @stmtS = 'CREATE SCHEMA '  
    select @stmtS = @stmtS + quotename(@name_in_db, ']')  
    select @stmtS = @stmtS + ' AUTHORIZATION '  
    select @stmtS = @stmtS + quotename(@name_in_db, ']')  
      
    BEGIN TRANSACTION  
      
    --  create the owner  
    exec (@stmtU)  
    if @@error <> 0  
    begin  
        ROLLBACK TRANSACTION  
        return (1)  
    end  
      
    --  create the Schema if one does not already exist with the same name and owner  
    declare @schema_uid int  
    declare @owner_uid  int  
    select @owner_uid  = principal_id from sys.database_principals where name = @name_in_db  
    select @schema_uid = principal_id from sys.schemas where name = @name_in_db  
    if (@schema_uid is null or        --  there is no schema since if there is one, it will have an owner  
        @schema_uid <> @owner_uid)  --  for error message  
    begin  
        exec (@stmtS)  
        if @@error <> 0  
        begin  
            ROLLBACK TRANSACTION  
            return (1)  
        end  
    end  
      
    COMMIT TRANSACTION  
  
    --  RETURN SUCCESS STATUS --   
    return (0)    --  sp_grantdbaccess