MySQL splicing table names recursively looking for child nodes and parent nodes

BEGINDeclareLevint;--Query Parent   SetLev=1; Drop Table if existsTMP1; CREATE TABLETMP1 (IDVARCHAR( +), Wl_codevarchar( -), Parentcodevarchar( +), LEVVINT); --Splicing table names and parameters in a stitched manner   SET @sqlcmd =CONCAT ('INSERT tmp1 SELECT id,wl_code,parentcode,1 from', TableName,'WHERE wl_code=', Wlcode); --Statement      PREPAREstmt from @sqlcmd; --Execute SQL   EXECUTEstmt; --deallocate PREPARE stmt;    --SELECT Row_count ();   whileRow_count ()>0 DoSetLev=Lev+1; --stitching SQL and Parameters        SET @sqlcmd =CONCAT ('INSERT tmp1 SELECT T.id,t.wl_code,t.parentcode,', Lev,' from', TableName,'T join Tmp1 A on T.wl_code=a.parentcode and levv=', Lev-1); PREPAREstmt from @sqlcmd; EXECUTEstmt; End  while ; --SELECT DISTINCT id,wl_code,parentcode from TMP1;--Query sub-levelSETLev=1;--Query sub-level   Drop Table if existsTMP2; CREATE TABLETMP2 (IDVARCHAR( +), Wl_codevarchar( -), Parentcodevarchar( +), LEVVINT);SET @sqlcmd =CONCAT ('INSERT tmp2 SELECT id,wl_code,parentcode,1 from', TableName,'WHERE parentcode=', Wlcode); PREPAREstmt from @sqlcmd; EXECUTEstmt;  whileRow_count ()>0 DoSetLev=Lev+1; SET @sqlcmd =CONCAT ('INSERT tmp2 SELECT T.id,t.wl_code,t.parentcode,', Lev,' from', TableName,'T join TMP2 A on T.parentcode=a.wl_code and levv=', Lev-1); PREPAREstmt from @sqlcmd; EXECUTEstmt; End  while ;--SELECT DISTINCT id,wl_code,parentcode from TMP2;SELECT DISTINCTId,wl_code,parentcode fromTmp1UNION  All SELECT DISTINCTId,wl_code,parentcode fromTmp2Order  byID;END

MySQL splicing table names recursively looking for child nodes and parent nodes