diff --git a/doc/src/sgml/ref/alter_table.sgml b/doc/src/sgml/ref/alter_table.sgml index be1647937dc..2cec1864dd0 100644 --- a/doc/src/sgml/ref/alter_table.sgml +++ b/doc/src/sgml/ref/alter_table.sgml @@ -616,9 +616,9 @@ WITH ( MODULUS numeric_literal, REM SET WITHOUT OIDS - Backward compatibility syntax for removing the oid - system column. As oid system columns cannot be added anymore, this never - has an effect. + Backward-compatible syntax for removing the oid + system column. As oid system columns cannot be + added anymore, this never has an effect. @@ -744,8 +744,7 @@ WITH ( MODULUS numeric_literal, REM This form links the table to a composite type as though CREATE TABLE OF had formed it. The table's list of column names and types - must precisely match that of the composite type; the presence of - an oid system column is permitted to differ. The table must + must precisely match that of the composite type. The table must not inherit from any other table. These restrictions ensure that CREATE TABLE OF would permit an equivalent table definition. @@ -1178,8 +1177,7 @@ WITH ( MODULUS numeric_literal, REM the column contents and the old type is either binary coercible to the new type or an unconstrained domain over the new type, a table rewrite is not needed; but any indexes on the affected columns must still be rebuilt. - Adding or removing a system oid column also requires - rewriting the entire table. Table and/or index rebuilds may take a + Table and/or index rebuilds may take a significant amount of time for a large table; and will temporarily require as much as double the disk space. @@ -1208,9 +1206,7 @@ WITH ( MODULUS numeric_literal, REM column. Thus, dropping a column is quick but it will not immediately reduce the on-disk size of your table, as the space occupied by the dropped column is not reclaimed. The space will be - reclaimed over time as existing rows are updated. (These statements do - not apply when dropping the system oid column; that is done - with an immediate rewrite.) + reclaimed over time as existing rows are updated.