diff options
Diffstat (limited to 'doc/src/sgml/syntax.sgml')
| -rw-r--r-- | doc/src/sgml/syntax.sgml | 38 |
1 files changed, 19 insertions, 19 deletions
diff --git a/doc/src/sgml/syntax.sgml b/doc/src/sgml/syntax.sgml index 9e086a58a7c..3ddedf57d49 100644 --- a/doc/src/sgml/syntax.sgml +++ b/doc/src/sgml/syntax.sgml @@ -1,4 +1,4 @@ -<!-- $PostgreSQL: pgsql/doc/src/sgml/syntax.sgml,v 1.112 2007/01/31 20:56:19 momjian Exp $ --> +<!-- $PostgreSQL: pgsql/doc/src/sgml/syntax.sgml,v 1.113 2007/02/01 00:28:18 momjian Exp $ --> <chapter id="sql-syntax"> <title>SQL Syntax</title> @@ -144,16 +144,16 @@ INSERT INTO MY_TABLE VALUES (3, 'hi there'); <primary>case sensitivity</primary> <secondary>of SQL commands</secondary> </indexterm> - Identifier and key word names are case insensitive. Therefore + Identifier and key word names are case insensitive. Therefore: <programlisting> UPDATE MY_TABLE SET A = 5; </programlisting> - can equivalently be written as + can equivalently be written as: <programlisting> uPDaTE my_TabLE SeT a = 5; </programlisting> A convention often used is to write key words in upper - case and names in lower case, e.g., + case and names in lower case, e.g.: <programlisting> UPDATE my_table SET a = 5; </programlisting> @@ -257,11 +257,11 @@ UPDATE "my_table" SET "a" = 5; SELECT 'foo' 'bar'; </programlisting> - is equivalent to + is equivalent to: <programlisting> SELECT 'foobar'; </programlisting> - but + but: <programlisting> SELECT 'foo' 'bar'; </programlisting> @@ -506,7 +506,7 @@ $function$ force a numeric value to be interpreted as a specific data type by casting it.<indexterm><primary>type cast</primary></indexterm> For example, you can force a numeric value to be treated as type - <type>real</> (<type>float4</>) by writing + <type>real</> (<type>float4</>) by writing: <programlisting> REAL '1.23' -- string style @@ -771,18 +771,18 @@ CAST ( '<replaceable>string</replaceable>' AS <replaceable>type</replaceable> ) <literal>></> have a different precedence than the Boolean operators <literal><=</> and <literal>>=</>. Also, you will sometimes need to add parentheses when using combinations of - binary and unary operators. For instance + binary and unary operators. For instance: <programlisting> SELECT 5 ! - 6; </programlisting> - will be parsed as + will be parsed as: <programlisting> SELECT 5 ! (- 6); </programlisting> because the parser has no idea — until it is too late — that <token>!</token> is defined as a postfix operator, not an infix one. To get the desired behavior in this case, you - must write + must write: <programlisting> SELECT (5 !) - 6; </programlisting> @@ -936,7 +936,7 @@ SELECT (5 !) - 6; <para> When a schema-qualified operator name is used in the - <literal>OPERATOR</> syntax, as for example in + <literal>OPERATOR</> syntax, as for example in: <programlisting> SELECT 3 OPERATOR(pg_catalog.+) 4; </programlisting> @@ -1133,7 +1133,7 @@ $<replaceable>number</replaceable> <para> For example, consider the definition of a function, - <function>dept</function>, as + <function>dept</function>, as: <programlisting> CREATE FUNCTION dept(text) RETURNS dept @@ -1175,7 +1175,7 @@ CREATE FUNCTION dept(text) RETURNS dept to be subscripted is just a column reference or positional parameter. Also, multiple subscripts can be concatenated when the original array is multidimensional. - For example, + For example: <programlisting> mytable.arraycolumn[4] @@ -1208,7 +1208,7 @@ $1[10:42] In general the row <replaceable>expression</replaceable> must be parenthesized, but the parentheses can be omitted when the expression to be selected from is just a table reference or positional parameter. - For example, + For example: <programlisting> mytable.mycolumn @@ -1494,7 +1494,7 @@ SELECT name, (SELECT max(pop) FROM cities WHERE cities.state = states.name) consists of the key word <literal>ARRAY</literal>, a left square bracket <literal>[</>, one or more expressions (separated by commas) for the array element values, and finally a right square bracket <literal>]</>. - For example, + For example: <programlisting> SELECT ARRAY[1,2,3+4]; array @@ -1597,7 +1597,7 @@ SELECT ARRAY(SELECT oid FROM pg_proc WHERE proname LIKE 'bytea%'); for its member fields. A row constructor consists of the key word <literal>ROW</literal>, a left parenthesis, zero or more expressions (separated by commas) for the row field values, and finally - a right parenthesis. For example, + a right parenthesis. For example: <programlisting> SELECT ROW(1,2.5,'this is a test'); </programlisting> @@ -1675,7 +1675,7 @@ SELECT getf1(CAST(ROW(11,'this is a test',2.5) AS myrowtype)); in a composite-type table column, or to be passed to a function that accepts a composite parameter. Also, it is possible to compare two row values or test a row with - <literal>IS NULL</> or <literal>IS NOT NULL</>, for example + <literal>IS NULL</> or <literal>IS NOT NULL</>, for example: <programlisting> SELECT ROW(1,2.5,'this is a test') = ROW(1, 3, 'not the same'); @@ -1705,12 +1705,12 @@ SELECT ROW(table.*) IS NULL FROM table; -- detect all-null rows <para> Furthermore, if the result of an expression can be determined by evaluating only some parts of it, then other subexpressions - might not be evaluated at all. For instance, if one wrote + might not be evaluated at all. For instance, if one wrote: <programlisting> SELECT true OR somefunc(); </programlisting> then <literal>somefunc()</literal> would (probably) not be called - at all. The same would be the case if one wrote + at all. The same would be the case if one wrote: <programlisting> SELECT somefunc() OR true; </programlisting> |