1.20. add_empty_table_to_replication( integer, integer, text, text, text, text )

Function Properties

Language: PLPGSQL

Return Type: bigint

Verify that a table is empty, and add it to replication. tab_idxname is optional - if NULL, then we use the primary key.

declare
  p_set_id alias for $1;
  p_tab_id alias for $2;
  p_nspname alias for $3;
  p_tabname alias for $4;
  p_idxname alias for $5;
  p_comment alias for $6;

  prec record;
  v_origin int4;
  v_isorigin boolean;
  v_fqname text;
  v_query text;
  v_rows integer;
  v_idxname text;

begin
-- Need to validate that the set exists; the set will tell us if this is the origin
  select set_origin into v_origin from sl_set where set_id = p_set_id;
  if not found then
	raise exception 'add_empty_table_to_replication: set % not found!', p_set_id;
  end if;

-- Need to be aware of whether or not this node is origin for the set
   v_isorigin := ( v_origin = getLocalNodeId('_schemadoc') );

   v_fqname := '"' || p_nspname || '"."' || p_tabname || '"';
-- Take out a lock on the table
   v_query := 'lock ' || v_fqname || ';';
   execute v_query;

   if v_isorigin then
	-- On the origin, verify that the table is empty, failing if it has any tuples
        v_query := 'select 1 as tuple from ' || v_fqname || ' limit 1;';
	execute v_query into prec;
        GET DIAGNOSTICS v_rows = ROW_COUNT;
	if v_rows = 0 then
		raise notice 'add_empty_table_to_replication: table % empty on origin - OK', v_fqname;
	else
		raise exception 'add_empty_table_to_replication: table % contained tuples on origin node %', v_fqname, v_origin;
	end if;
   else
	-- On other nodes, TRUNCATE the table
        v_query := 'truncate ' || v_fqname || ';';
	execute v_query;
   end if;
-- If p_idxname is NULL, then look up the PK index, and RAISE EXCEPTION if one does not exist
   if p_idxname is NULL then
	select c2.relname into prec from pg_catalog.pg_index i, pg_catalog.pg_class c1, pg_catalog.pg_class c2, pg_catalog.pg_namespace n where i.indrelid = c1.oid and i.indexrelid = c2.oid and c1.relname = p_tabname and i.indisprimary and n.nspname = p_nspname and n.oid = c1.relnamespace;
	if not found then
		raise exception 'add_empty_table_to_replication: table % has no primary key and no candidate specified!', v_fqname;
	else
		v_idxname := prec.relname;
	end if;
   else
	v_idxname := p_idxname;
   end if;
   perform setAddTable_int(p_set_id, p_tab_id, v_fqname, v_idxname, p_comment);
   return alterTableRestore(p_tab_id);
end