diff options
Diffstat (limited to 'doc/src/sgml/ddl.sgml')
| -rw-r--r-- | doc/src/sgml/ddl.sgml | 30 |
1 files changed, 15 insertions, 15 deletions
diff --git a/doc/src/sgml/ddl.sgml b/doc/src/sgml/ddl.sgml index 0461c8b8b2..a3c9552117 100644 --- a/doc/src/sgml/ddl.sgml +++ b/doc/src/sgml/ddl.sgml @@ -1,4 +1,4 @@ -<!-- $PostgreSQL: pgsql/doc/src/sgml/ddl.sgml,v 1.48 2005/11/04 02:56:30 tgl Exp $ --> +<!-- $PostgreSQL: pgsql/doc/src/sgml/ddl.sgml,v 1.49 2005/11/04 23:13:59 petere Exp $ --> <chapter id="ddl"> <title>Data Definition</title> @@ -202,7 +202,7 @@ CREATE TABLE products ( The default value may be an expression, which will be evaluated whenever the default value is inserted (<emphasis>not</emphasis> when the table is created). A common example - is that a timestamp column may have a default of <literal>now()</>, + is that a <type>timestamp</type> column may have a default of <literal>now()</>, so that it gets set to the time of row insertion. Another common example is generating a <quote>serial number</> for each row. In <productname>PostgreSQL</productname> this is typically done by @@ -1157,7 +1157,7 @@ SELECT name, altitude </note> <para> - Inheritance does not automatically propogate data from + Inheritance does not automatically propagate data from <command>INSERT</command> or <command>COPY</command> commands to other tables in the inheritance hierarchy. In our example, the following <command>INSERT</command> statement will fail: @@ -1221,12 +1221,12 @@ WHERE c.altitude > 500 and c.tableoid = p.oid; <para> As shown above, a child table may locally define columns as well as inheriting them from their parents. However, a locally defined - column cannot override the datatype of an inherited column of the + column cannot override the data type of an inherited column of the same name. A table can inherit from a table that has itself inherited from other tables. A table can also inherit from more than one parent table, in which case it inherits the union of the columns defined by the parent tables. Inherited columns with - duplicate names and datatypes will be merged so that only a single + duplicate names and data types will be merged so that only a single column is stored. </para> @@ -1498,7 +1498,7 @@ CHECK ( county IN ( 'Oxfordshire','Buckinghamshire','Warwickshire' )) CHECK ( outletID BETWEEN 1 AND 99 ) </programlisting> - These can be linked together with the boolean operators + These can be linked together with the Boolean operators <literal>AND</literal> and <literal>OR</literal> to form complex constraints. Note that there is no difference in syntax between range and list partitioning; those terms are @@ -1722,10 +1722,10 @@ DO INSTEAD <listitem> <para> - For some datatypes you must explicitly coerce the constant - values into the datatype of the column. The following constraint + For some data types you must explicitly coerce the constant + values into the data type of the column. The following constraint will work if <varname>x</varname> is an <type>integer</type> - datatype, but not if <varname>x</varname> is a + data type, but not if <varname>x</varname> is a <type>bigint</type>: <programlisting> CHECK ( x = 1 ) @@ -1734,9 +1734,9 @@ CHECK ( x = 1 ) <programlisting> CHECK ( x = 1::bigint ) </programlisting> - The problem is not limited to the <type>bigint</type> datatype - — it can occur whenever the default datatype of the - constant does not match the datatype of the column to which it + The problem is not limited to the <type>bigint</type> data type + — it can occur whenever the default data type of the + constant does not match the data type of the column to which it is being compared. </para> </listitem> @@ -1849,7 +1849,7 @@ ANALYZE measurement; <listitem> <para> Constraint exclusion only works when the query directly matches - a constant. A constant bound to a parameterised query will not + a constant. A constant bound to a parameterized query will not work in the same way since the plan is fixed and would need to vary with each execution. Also, stable constants such as <literal>CURRENT_DATE</literal> may not be used, since these are @@ -1860,8 +1860,8 @@ ANALYZE measurement; <listitem> <para> - UPDATEs and DELETEs against the master table do not perform - constraint exclusion. + <command>UPDATE</command> and <command>DELETE</command> commands + against the master table do not perform constraint exclusion. </para> </listitem> |