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11th chunk of `doc/src/sgml/ecpg.sgml`
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 types, such
    as <type>timestamp</type> and <type>numeric</type> can only be
    accessed through special library functions; see
    <xref linkend="ecpg-special-types"/>.
   </para>

   <para>
    <xref linkend="ecpg-datatype-hostvars-table"/> shows which PostgreSQL
    data types correspond to which C data types.  When you wish to
    send or receive a value of a given PostgreSQL data type, you
    should declare a C variable of the corresponding C data type in
    the declare section.
   </para>

   <table id="ecpg-datatype-hostvars-table">
    <title>Mapping Between PostgreSQL Data Types and C Variable Types</title>
    <tgroup cols="2">
     <thead>
      <row>
       <entry>PostgreSQL data type</entry>
       <entry>Host variable type</entry>
      </row>
     </thead>

     <tbody>
      <row>
       <entry><type>smallint</type></entry>
       <entry><type>short</type></entry>
      </row>

      <row>
       <entry><type>integer</type></entry>
       <entry><type>int</type></entry>
      </row>

      <row>
       <entry><type>bigint</type></entry>
       <entry><type>long long int</type></entry>
      </row>

      <row>
       <entry><type>decimal</type></entry>
       <entry><type>decimal</type><footnote id="ecpg-datatype-table-fn"><para>This type can only be accessed through special library functions; see <xref linkend="ecpg-special-types"/>.</para></footnote></entry>
      </row>

      <row>
       <entry><type>numeric</type></entry>
       <entry><type>numeric</type><footnoteref linkend="ecpg-datatype-table-fn"/></entry>
      </row>

      <row>
       <entry><type>real</type></entry>
       <entry><type>float</type></entry>
      </row>

      <row>
       <entry><type>double precision</type></entry>
       <entry><type>double</type></entry>
      </row>

      <row>
       <entry><type>smallserial</type></entry>
       <entry><type>short</type></entry>
      </row>

      <row>
       <entry><type>serial</type></entry>
       <entry><type>int</type></entry>
      </row>

      <row>
       <entry><type>bigserial</type></entry>
       <entry><type>long long int</type></entry>
      </row>

      <row>
       <entry><type>oid</type></entry>
       <entry><type>unsigned int</type></entry>
      </row>

      <row>
       <entry><type>character(<replaceable>n</replaceable>)</type>, <type>varchar(<replaceable>n</replaceable>)</type>, <type>text</type></entry>
       <entry><type>char[<replaceable>n</replaceable>+1]</type>, <type>VARCHAR[<replaceable>n</replaceable>+1]</type></entry>
      </row>

      <row>
       <entry><type>name</type></entry>
       <entry><type>char[NAMEDATALEN]</type></entry>
      </row>

      <row>
       <entry><type>timestamp</type></entry>
       <entry><type>timestamp</type><footnoteref linkend="ecpg-datatype-table-fn"/></entry>
      </row>

      <row>
       <entry><type>interval</type></entry>
       <entry><type>interval</type><footnoteref linkend="ecpg-datatype-table-fn"/></entry>
      </row>

      <row>
       <entry><type>date</type></entry>
       <entry><type>date</type><footnoteref linkend="ecpg-datatype-table-fn"/></entry>
      </row>

      <row>
       <entry><type>boolean</type></entry>
       <entry><type>bool</type><footnote><para>declared in <filename>ecpglib.h</filename> if not native</para></footnote></entry>
      </row>

      <row>
       <entry><type>bytea</type></entry>
       <entry><type>char *</type>, <type>bytea[<replaceable>n</replaceable>]</type></entry>
      </row>
     </tbody>
    </tgroup>
   </table>

   <sect3 id="ecpg-char">
    <title>Handling Character Strings</title>

    <para>
     To handle SQL character string data types, such
     as <type>varchar</type> and <type>text</type>, there are two
     possible ways to declare the host variables.
    </para>

    <para>
     One way is using <type>char[]</type>, an array
     of <type>char</type>, which is the most common way to handle
     character data in C.
<programlisting>
EXEC SQL BEGIN
Title: ECPG: PostgreSQL to C Data Type Mapping and Handling Character Strings
Summary
This section provides a table mapping PostgreSQL data types to corresponding C variable types for ECPG applications. It specifies the correct C data types to use when sending or receiving values of specific PostgreSQL data types in the declare section. It also details how certain data types like `timestamp`, `numeric`, `decimal`, `interval`, and `date` require special library functions for access. The section further focuses on handling SQL character string data types such as `varchar` and `text`, introducing the use of `char[]` for character data in C.