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Fix indentation of verbatim block elements
Block elements with verbatim formatting (literallayout, programlisting, screen, synopsis) should be aligned at column 0 independent of the surrounding SGML, because whitespace is significant, and indenting them creates erratic whitespace in the output. The CSS stylesheets already take care of indenting the output. Assorted markup improvements to go along with it.
This commit is contained in:
Peter Eisentraut
@@ -1,4 +1,4 @@
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<!-- $PostgreSQL: pgsql/doc/src/sgml/sql.sgml,v 1.48 2009/04/27 16:27:36 momjian Exp $ -->
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<!-- $PostgreSQL: pgsql/doc/src/sgml/sql.sgml,v 1.49 2010/07/29 19:34:40 petere Exp $ -->
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<chapter id="sql-intro">
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<title>SQL</title>
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@@ -151,7 +151,7 @@
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<example>
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<title id="supplier-fig">The Suppliers and Parts Database</title>
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<programlisting>
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<screen>
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SUPPLIER: SELLS:
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SNO | SNAME | CITY SNO | PNO
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----+---------+-------- -----+-----
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@@ -168,7 +168,7 @@ PART: 4 | 3
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2 | Nut | 8
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3 | Bolt | 15
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4 | Cam | 25
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</programlisting>
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</screen>
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</example>
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</para>
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@@ -530,14 +530,14 @@ attributes are taken from. We often write a relation scheme as
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necessary for a join.
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Let the following two tables be given:
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<programlisting>
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<screen>
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R: S:
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A | B | C C | D | E
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---+---+--- ---+---+---
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1 | 2 | 3 3 | a | b
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4 | 5 | 6 6 | c | d
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7 | 8 | 9
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</programlisting>
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</screen>
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</para>
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</example>
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@@ -546,7 +546,7 @@ R: S:
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<classname>R</classname> × <classname>S</classname> and
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get:
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<programlisting>
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<screen>
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R x S:
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A | B | R.C | S.C | D | E
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---+---+-----+-----+---+---
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@@ -556,7 +556,7 @@ R x S:
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4 | 5 | 6 | 6 | c | d
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7 | 8 | 9 | 3 | a | b
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7 | 8 | 9 | 6 | c | d
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</programlisting>
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</screen>
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</para>
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<para>
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@@ -564,12 +564,12 @@ R x S:
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σ<subscript>R.C=S.C</subscript>(R × S)
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we get:
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<programlisting>
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<screen>
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A | B | R.C | S.C | D | E
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---+---+-----+-----+---+---
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1 | 2 | 3 | 3 | a | b
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4 | 5 | 6 | 6 | c | d
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</programlisting>
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</screen>
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</para>
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<para>
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@@ -579,12 +579,12 @@ R x S:
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π<subscript>R.A,R.B,R.C,S.D,S.E</subscript>(σ<subscript>R.C=S.C</subscript>(R × S))
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and get:
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<programlisting>
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<screen>
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A | B | C | D | E
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---+---+---+---+---
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1 | 2 | 3 | a | b
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4 | 5 | 6 | c | d
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</programlisting>
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</screen>
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</para>
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</listitem>
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@@ -596,9 +596,9 @@ R x S:
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C and D.
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Then we define the division as:
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<programlisting>
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<programlisting>
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R ÷ S = {t ∣ ∀ t<subscript>s</subscript> ∈ S ∃ t<subscript>r</subscript> ∈ R
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</programlisting>
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</programlisting>
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such that
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t<subscript>r</subscript>(A,B)=t∧t<subscript>r</subscript>(C,D)=t<subscript>s</subscript>}
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@@ -615,7 +615,7 @@ t<subscript>r</subscript>(A,B)=t∧t<subscript>r</subscript>(C,D)=t<subscript>
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<para id="divide-example">
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Given the following tables
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<programlisting>
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<screen>
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R: S:
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A | B | C | D C | D
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---+---+---+--- ---+---
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@@ -625,17 +625,17 @@ R: S:
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e | d | c | d
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e | d | e | f
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a | b | d | e
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</programlisting>
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</screen>
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R ÷ S
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is derived as
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<programlisting>
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<screen>
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A | B
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---+---
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a | b
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e | d
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</programlisting>
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</screen>
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</para>
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</listitem>
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</itemizedlist>
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@@ -659,9 +659,9 @@ R: S:
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This question can be answered
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using relational algebra by the following operation:
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<programlisting>
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<programlisting>
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π<subscript>SUPPLIER.SNAME</subscript>(σ<subscript>PART.PNAME='Screw'</subscript>(SUPPLIER ∏ SELLS ∏ PART))
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</programlisting>
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</programlisting>
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</para>
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<para>
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@@ -670,12 +670,12 @@ R: S:
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(<xref linkend="supplier-fig" endterm="supplier-fig">)
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we will obtain the following result:
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<programlisting>
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<screen>
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SNAME
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-------
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Smith
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Adams
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</programlisting>
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</screen>
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</para>
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</example>
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</sect2>
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@@ -724,9 +724,9 @@ R: S:
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The queries used in <acronym>TRC</acronym> are of the following
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form:
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<programlisting>
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<programlisting>
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x(A) ∣ F(x)
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</programlisting>
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</programlisting>
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where <literal>x</literal> is a tuple variable
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<classname>A</classname> is a set of attributes and <literal>F</literal> is a
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@@ -739,12 +739,12 @@ x(A) ∣ F(x)
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<xref linkend="suppl-rel-alg" endterm="suppl-rel-alg">
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using <acronym>TRC</acronym> we formulate the following query:
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<programlisting>
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<programlisting>
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{x(SNAME) ∣ x ∈ SUPPLIER ∧
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∃ y ∈ SELLS ∃ z ∈ PART (y(SNO)=x(SNO) ∧
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z(PNO)=y(PNO) ∧
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z(PNAME)='Screw')}
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</programlisting>
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</programlisting>
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</para>
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<para>
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@@ -813,9 +813,9 @@ x(A) ∣ F(x)
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to involve
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arithmetic operations as well as comparisons, e.g.:
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<programlisting>
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<programlisting>
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A < B + 3.
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</programlisting>
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</programlisting>
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Note
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that + or other arithmetic operators appear neither in relational
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@@ -851,7 +851,7 @@ A < B + 3.
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<command>SELECT</command> statement,
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used to retrieve data. The syntax is:
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<synopsis>
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<synopsis>
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SELECT [ ALL | DISTINCT [ ON ( <replaceable class="PARAMETER">expression</replaceable> [, ...] ) ] ]
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* | <replaceable class="PARAMETER">expression</replaceable> [ [ AS ] <replaceable class="PARAMETER">output_name</replaceable> ] [, ...]
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[ INTO [ TEMPORARY | TEMP ] [ TABLE ] <replaceable class="PARAMETER">new_table</replaceable> ]
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@@ -864,7 +864,7 @@ SELECT [ ALL | DISTINCT [ ON ( <replaceable class="PARAMETER">expression</replac
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[ LIMIT { <replaceable class="PARAMETER">count</replaceable> | ALL } ]
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[ OFFSET <replaceable class="PARAMETER">start</replaceable> ]
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[ FOR { UPDATE | SHARE } [ OF <replaceable class="parameter">table_name</replaceable> [, ...] ] [ NOWAIT ] [...] ]
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</synopsis>
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</synopsis>
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</para>
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<para>
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@@ -886,19 +886,19 @@ SELECT [ ALL | DISTINCT [ ON ( <replaceable class="PARAMETER">expression</replac
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To retrieve all tuples from table PART where the attribute PRICE is
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greater than 10 we formulate the following query:
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<programlisting>
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<programlisting>
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SELECT * FROM PART
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WHERE PRICE > 10;
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</programlisting>
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</programlisting>
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and get the table:
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<programlisting>
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<screen>
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PNO | PNAME | PRICE
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-----+---------+--------
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3 | Bolt | 15
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4 | Cam | 25
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</programlisting>
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</screen>
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</para>
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<para>
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@@ -907,20 +907,20 @@ SELECT * FROM PART
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only the attributes PNAME and PRICE from table PART we use the
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statement:
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<programlisting>
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<programlisting>
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SELECT PNAME, PRICE
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FROM PART
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WHERE PRICE > 10;
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</programlisting>
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</programlisting>
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In this case the result is:
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<programlisting>
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<screen>
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PNAME | PRICE
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--------+--------
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Bolt | 15
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Cam | 25
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</programlisting>
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</screen>
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Note that the <acronym>SQL</acronym> <command>SELECT</command>
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corresponds to the <quote>projection</quote> in relational algebra
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@@ -932,20 +932,20 @@ SELECT PNAME, PRICE
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The qualifications in the WHERE clause can also be logically connected
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using the keywords OR, AND, and NOT:
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<programlisting>
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<programlisting>
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SELECT PNAME, PRICE
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FROM PART
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WHERE PNAME = 'Bolt' AND
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(PRICE = 0 OR PRICE <= 15);
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</programlisting>
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</programlisting>
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will lead to the result:
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<programlisting>
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<screen>
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PNAME | PRICE
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--------+--------
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Bolt | 15
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</programlisting>
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</screen>
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</para>
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<para>
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@@ -953,21 +953,21 @@ SELECT PNAME, PRICE
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clause. For example if we want to know how much it would cost if we
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take two pieces of a part we could use the following query:
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<programlisting>
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<programlisting>
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SELECT PNAME, PRICE * 2 AS DOUBLE
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FROM PART
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WHERE PRICE * 2 < 50;
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</programlisting>
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</programlisting>
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and we get:
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<programlisting>
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<screen>
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PNAME | DOUBLE
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--------+---------
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Screw | 20
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Nut | 16
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Bolt | 30
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</programlisting>
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</screen>
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Note that the word DOUBLE after the keyword AS is the new title of the
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second column. This technique can be used for every element of the
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@@ -992,16 +992,16 @@ SELECT PNAME, PRICE * 2 AS DOUBLE
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To join the three tables SUPPLIER, PART and SELLS over their common
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attributes we formulate the following statement:
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<programlisting>
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<programlisting>
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SELECT S.SNAME, P.PNAME
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FROM SUPPLIER S, PART P, SELLS SE
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WHERE S.SNO = SE.SNO AND
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P.PNO = SE.PNO;
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</programlisting>
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</programlisting>
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and get the following table as a result:
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<programlisting>
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<screen>
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SNAME | PNAME
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-------+-------
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Smith | Screw
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@@ -1012,7 +1012,7 @@ SELECT S.SNAME, P.PNAME
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Blake | Nut
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Blake | Bolt
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Blake | Cam
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</programlisting>
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</screen>
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</para>
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<para>
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@@ -1034,13 +1034,13 @@ SELECT S.SNAME, P.PNAME
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<para>
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Another way to perform joins is to use the SQL JOIN syntax as follows:
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<programlisting>
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select sname, pname from supplier
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<programlisting>
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SELECT sname, pname from supplier
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JOIN sells USING (sno)
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JOIN part USING (pno);
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</programlisting>
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</programlisting>
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giving again:
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<programlisting>
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<screen>
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sname | pname
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-------+-------
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Smith | Screw
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@@ -1052,7 +1052,7 @@ select sname, pname from supplier
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Jones | Cam
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Blake | Cam
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(8 rows)
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</programlisting>
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</screen>
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</para>
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<para>
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@@ -1267,38 +1267,38 @@ select sname, pname from supplier
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If we want to know the average cost of all parts in table PART we use
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the following query:
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<programlisting>
|
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<programlisting>
|
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SELECT AVG(PRICE) AS AVG_PRICE
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FROM PART;
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</programlisting>
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</programlisting>
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</para>
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<para>
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The result is:
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<programlisting>
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<screen>
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AVG_PRICE
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-----------
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14.5
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</programlisting>
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</screen>
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</para>
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<para>
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If we want to know how many parts are defined in table PART we use
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the statement:
|
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|
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<programlisting>
|
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<programlisting>
|
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SELECT COUNT(PNO)
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FROM PART;
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</programlisting>
|
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</programlisting>
|
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|
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and get:
|
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|
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<programlisting>
|
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<screen>
|
||||
COUNT
|
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-------
|
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4
|
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</programlisting>
|
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</screen>
|
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|
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</para>
|
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</example>
|
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@@ -1335,23 +1335,23 @@ SELECT COUNT(PNO)
|
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If we want to know how many parts are sold by every supplier we
|
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formulate the query:
|
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|
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<programlisting>
|
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<programlisting>
|
||||
SELECT S.SNO, S.SNAME, COUNT(SE.PNO)
|
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FROM SUPPLIER S, SELLS SE
|
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WHERE S.SNO = SE.SNO
|
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GROUP BY S.SNO, S.SNAME;
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
|
||||
and get:
|
||||
|
||||
<programlisting>
|
||||
<screen>
|
||||
SNO | SNAME | COUNT
|
||||
-----+-------+-------
|
||||
1 | Smith | 2
|
||||
2 | Jones | 1
|
||||
3 | Adams | 2
|
||||
4 | Blake | 3
|
||||
</programlisting>
|
||||
</screen>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
@@ -1359,7 +1359,7 @@ SELECT S.SNO, S.SNAME, COUNT(SE.PNO)
|
||||
First the join of the
|
||||
tables SUPPLIER and SELLS is derived:
|
||||
|
||||
<programlisting>
|
||||
<screen>
|
||||
S.SNO | S.SNAME | SE.PNO
|
||||
-------+---------+--------
|
||||
1 | Smith | 1
|
||||
@@ -1370,14 +1370,14 @@ SELECT S.SNO, S.SNAME, COUNT(SE.PNO)
|
||||
4 | Blake | 2
|
||||
4 | Blake | 3
|
||||
4 | Blake | 4
|
||||
</programlisting>
|
||||
</screen>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
Next we partition the tuples into groups by putting all tuples
|
||||
together that agree on both attributes S.SNO and S.SNAME:
|
||||
|
||||
<programlisting>
|
||||
<screen>
|
||||
S.SNO | S.SNAME | SE.PNO
|
||||
-------+---------+--------
|
||||
1 | Smith | 1
|
||||
@@ -1391,7 +1391,7 @@ SELECT S.SNO, S.SNAME, COUNT(SE.PNO)
|
||||
4 | Blake | 2
|
||||
| 3
|
||||
| 4
|
||||
</programlisting>
|
||||
</screen>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
@@ -1442,23 +1442,23 @@ SELECT S.SNO, S.SNAME, COUNT(SE.PNO)
|
||||
If we want only those suppliers selling more than one part we use the
|
||||
query:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
SELECT S.SNO, S.SNAME, COUNT(SE.PNO)
|
||||
FROM SUPPLIER S, SELLS SE
|
||||
WHERE S.SNO = SE.SNO
|
||||
GROUP BY S.SNO, S.SNAME
|
||||
HAVING COUNT(SE.PNO) > 1;
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
|
||||
and get:
|
||||
|
||||
<programlisting>
|
||||
<screen>
|
||||
SNO | SNAME | COUNT
|
||||
-----+-------+-------
|
||||
1 | Smith | 2
|
||||
3 | Adams | 2
|
||||
4 | Blake | 3
|
||||
</programlisting>
|
||||
</screen>
|
||||
</para>
|
||||
</example>
|
||||
</para>
|
||||
@@ -1481,23 +1481,23 @@ SELECT S.SNO, S.SNAME, COUNT(SE.PNO)
|
||||
If we want to know all parts having a greater price than the part
|
||||
named 'Screw' we use the query:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
SELECT *
|
||||
FROM PART
|
||||
WHERE PRICE > (SELECT PRICE FROM PART
|
||||
WHERE PNAME='Screw');
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
The result is:
|
||||
|
||||
<programlisting>
|
||||
<screen>
|
||||
PNO | PNAME | PRICE
|
||||
-----+---------+--------
|
||||
3 | Bolt | 15
|
||||
4 | Cam | 25
|
||||
</programlisting>
|
||||
</screen>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
@@ -1519,13 +1519,13 @@ SELECT *
|
||||
If we want to know all suppliers that do not sell any part
|
||||
(e.g., to be able to remove these suppliers from the database) we use:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
SELECT *
|
||||
FROM SUPPLIER S
|
||||
WHERE NOT EXISTS
|
||||
(SELECT * FROM SELLS SE
|
||||
WHERE SE.SNO = S.SNO);
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
@@ -1559,14 +1559,14 @@ SELECT *
|
||||
If we want to know the highest average part price among all our
|
||||
suppliers, we cannot write MAX(AVG(PRICE)), but we can write:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
SELECT MAX(subtable.avgprice)
|
||||
FROM (SELECT AVG(P.PRICE) AS avgprice
|
||||
FROM SUPPLIER S, PART P, SELLS SE
|
||||
WHERE S.SNO = SE.SNO AND
|
||||
P.PNO = SE.PNO
|
||||
GROUP BY S.SNO) subtable;
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
|
||||
The subquery returns one row per supplier (because of its GROUP BY)
|
||||
and then we aggregate over those rows in the outer query.
|
||||
@@ -1588,7 +1588,7 @@ SELECT MAX(subtable.avgprice)
|
||||
<para>
|
||||
The following query is an example for UNION:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
SELECT S.SNO, S.SNAME, S.CITY
|
||||
FROM SUPPLIER S
|
||||
WHERE S.SNAME = 'Jones'
|
||||
@@ -1596,22 +1596,22 @@ UNION
|
||||
SELECT S.SNO, S.SNAME, S.CITY
|
||||
FROM SUPPLIER S
|
||||
WHERE S.SNAME = 'Adams';
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
|
||||
gives the result:
|
||||
|
||||
<programlisting>
|
||||
<screen>
|
||||
SNO | SNAME | CITY
|
||||
-----+-------+--------
|
||||
2 | Jones | Paris
|
||||
3 | Adams | Vienna
|
||||
</programlisting>
|
||||
</screen>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
Here is an example for INTERSECT:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
SELECT S.SNO, S.SNAME, S.CITY
|
||||
FROM SUPPLIER S
|
||||
WHERE S.SNO > 1
|
||||
@@ -1619,15 +1619,15 @@ INTERSECT
|
||||
SELECT S.SNO, S.SNAME, S.CITY
|
||||
FROM SUPPLIER S
|
||||
WHERE S.SNO < 3;
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
|
||||
gives the result:
|
||||
|
||||
<programlisting>
|
||||
<screen>
|
||||
SNO | SNAME | CITY
|
||||
-----+-------+--------
|
||||
2 | Jones | Paris
|
||||
</programlisting>
|
||||
</screen>
|
||||
|
||||
The only tuple returned by both parts of the query is the one having SNO=2.
|
||||
</para>
|
||||
@@ -1635,7 +1635,7 @@ INTERSECT
|
||||
<para>
|
||||
Finally an example for EXCEPT:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
SELECT S.SNO, S.SNAME, S.CITY
|
||||
FROM SUPPLIER S
|
||||
WHERE S.SNO > 1
|
||||
@@ -1643,16 +1643,16 @@ EXCEPT
|
||||
SELECT S.SNO, S.SNAME, S.CITY
|
||||
FROM SUPPLIER S
|
||||
WHERE S.SNO > 3;
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
|
||||
gives the result:
|
||||
|
||||
<programlisting>
|
||||
<screen>
|
||||
SNO | SNAME | CITY
|
||||
-----+-------+--------
|
||||
2 | Jones | Paris
|
||||
3 | Adams | Vienna
|
||||
</programlisting>
|
||||
</screen>
|
||||
</para>
|
||||
</example>
|
||||
</para>
|
||||
@@ -1675,12 +1675,12 @@ EXCEPT
|
||||
one that creates a new relation (a new table). The syntax of the
|
||||
<command>CREATE TABLE</command> command is:
|
||||
|
||||
<synopsis>
|
||||
<synopsis>
|
||||
CREATE TABLE <replaceable class="parameter">table_name</replaceable>
|
||||
(<replaceable class="parameter">name_of_attr_1</replaceable> <replaceable class="parameter">type_of_attr_1</replaceable>
|
||||
[, <replaceable class="parameter">name_of_attr_2</replaceable> <replaceable class="parameter">type_of_attr_2</replaceable>
|
||||
[, ...]]);
|
||||
</synopsis>
|
||||
</synopsis>
|
||||
|
||||
<example>
|
||||
<title id="table-create">Table Creation</title>
|
||||
@@ -1690,25 +1690,25 @@ CREATE TABLE <replaceable class="parameter">table_name</replaceable>
|
||||
<xref linkend="supplier-fig" endterm="supplier-fig"> the
|
||||
following <acronym>SQL</acronym> statements are used:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
CREATE TABLE SUPPLIER
|
||||
(SNO INTEGER,
|
||||
SNAME VARCHAR(20),
|
||||
CITY VARCHAR(20));
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
CREATE TABLE PART
|
||||
(PNO INTEGER,
|
||||
PNAME VARCHAR(20),
|
||||
PRICE DECIMAL(4 , 2));
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
CREATE TABLE SELLS
|
||||
(SNO INTEGER,
|
||||
PNO INTEGER);
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
</para>
|
||||
</example>
|
||||
</para>
|
||||
@@ -1791,10 +1791,10 @@ CREATE TABLE SELLS
|
||||
To create an index in <acronym>SQL</acronym>
|
||||
the <command>CREATE INDEX</command> command is used. The syntax is:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
CREATE INDEX <replaceable class="parameter">index_name</replaceable>
|
||||
ON <replaceable class="parameter">table_name</replaceable> ( <replaceable class="parameter">name_of_attribute</replaceable> );
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
@@ -1805,9 +1805,9 @@ CREATE INDEX <replaceable class="parameter">index_name</replaceable>
|
||||
To create an index named I on attribute SNAME of relation SUPPLIER
|
||||
we use the following statement:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
CREATE INDEX I ON SUPPLIER (SNAME);
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
@@ -1855,10 +1855,10 @@ CREATE INDEX I ON SUPPLIER (SNAME);
|
||||
command is used to define a view. The syntax
|
||||
is:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
CREATE VIEW <replaceable class="parameter">view_name</replaceable>
|
||||
AS <replaceable class="parameter">select_stmt</replaceable>
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
|
||||
where <replaceable class="parameter">select_stmt</replaceable>
|
||||
is a valid select statement as defined
|
||||
@@ -1874,14 +1874,14 @@ CREATE VIEW <replaceable class="parameter">view_name</replaceable>
|
||||
the tables from
|
||||
<xref linkend="supplier-fig" endterm="supplier-fig"> again):
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
CREATE VIEW London_Suppliers
|
||||
AS SELECT S.SNAME, P.PNAME
|
||||
FROM SUPPLIER S, PART P, SELLS SE
|
||||
WHERE S.SNO = SE.SNO AND
|
||||
P.PNO = SE.PNO AND
|
||||
S.CITY = 'London';
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
@@ -1889,18 +1889,18 @@ CREATE VIEW London_Suppliers
|
||||
<classname>London_Suppliers</classname> as
|
||||
if it were another base table:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
SELECT * FROM London_Suppliers
|
||||
WHERE PNAME = 'Screw';
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
|
||||
which will return the following table:
|
||||
|
||||
<programlisting>
|
||||
<screen>
|
||||
SNAME | PNAME
|
||||
-------+-------
|
||||
Smith | Screw
|
||||
</programlisting>
|
||||
</screen>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
@@ -1922,34 +1922,34 @@ SELECT * FROM London_Suppliers
|
||||
To destroy a table (including all tuples stored in that table) the
|
||||
<command>DROP TABLE</command> command is used:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
DROP TABLE <replaceable class="parameter">table_name</replaceable>;
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
To destroy the SUPPLIER table use the following statement:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
DROP TABLE SUPPLIER;
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
The <command>DROP INDEX</command> command is used to destroy an index:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
DROP INDEX <replaceable class="parameter">index_name</replaceable>;
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
Finally to destroy a given view use the command <command>DROP
|
||||
VIEW</command>:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
DROP VIEW <replaceable class="parameter">view_name</replaceable>;
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
</para>
|
||||
</sect3>
|
||||
</sect2>
|
||||
@@ -1966,11 +1966,11 @@ DROP VIEW <replaceable class="parameter">view_name</replaceable>;
|
||||
with tuples using the command <command>INSERT INTO</command>.
|
||||
The syntax is:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
INSERT INTO <replaceable class="parameter">table_name</replaceable> (<replaceable class="parameter">name_of_attr_1</replaceable>
|
||||
[, <replaceable class="parameter">name_of_attr_2</replaceable> [,...]])
|
||||
VALUES (<replaceable class="parameter">val_attr_1</replaceable> [, <replaceable class="parameter">val_attr_2</replaceable> [, ...]]);
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
@@ -1978,19 +1978,19 @@ INSERT INTO <replaceable class="parameter">table_name</replaceable> (<replaceabl
|
||||
<xref linkend="supplier-fig" endterm="supplier-fig">) we use the
|
||||
following statement:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
INSERT INTO SUPPLIER (SNO, SNAME, CITY)
|
||||
VALUES (1, 'Smith', 'London');
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
To insert the first tuple into the relation SELLS we use:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
INSERT INTO SELLS (SNO, PNO)
|
||||
VALUES (1, 1);
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
</para>
|
||||
</sect3>
|
||||
|
||||
@@ -2001,23 +2001,23 @@ INSERT INTO SELLS (SNO, PNO)
|
||||
To change one or more attribute values of tuples in a relation the
|
||||
<command>UPDATE</command> command is used. The syntax is:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
UPDATE <replaceable class="parameter">table_name</replaceable>
|
||||
SET <replaceable class="parameter">name_of_attr_1</replaceable> = <replaceable class="parameter">value_1</replaceable>
|
||||
[, ... [, <replaceable class="parameter">name_of_attr_k</replaceable> = <replaceable class="parameter">value_k</replaceable>]]
|
||||
WHERE <replaceable class="parameter">condition</replaceable>;
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
To change the value of attribute PRICE of the part 'Screw' in the
|
||||
relation PART we use:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
UPDATE PART
|
||||
SET PRICE = 15
|
||||
WHERE PNAME = 'Screw';
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
@@ -2033,20 +2033,20 @@ UPDATE PART
|
||||
To delete a tuple from a particular table use the command DELETE
|
||||
FROM. The syntax is:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
DELETE FROM <replaceable class="parameter">table_name</replaceable>
|
||||
WHERE <replaceable class="parameter">condition</replaceable>;
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
To delete the supplier called 'Smith' of the table SUPPLIER the
|
||||
following statement is used:
|
||||
|
||||
<programlisting>
|
||||
<programlisting>
|
||||
DELETE FROM SUPPLIER
|
||||
WHERE SNAME = 'Smith';
|
||||
</programlisting>
|
||||
</programlisting>
|
||||
</para>
|
||||
</sect3>
|
||||
</sect2>
|
||||
|
||||
Reference in New Issue
Block a user