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<concept id="GUID-F5B0FE6A-6DE6-56B5-89A5-684CD2602B40" xml:lang="en"><title>Implementation

limits</title><shortdesc>This document lists the maximum number of tables, columns, indexes

and so on per database.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

<p>The number of tables in a database is limited only by available resources.</p>

<p>The number of columns in a table is usually limited by a maximum record

size of 8200 bytes (just over 8Kb), e.g. a table could have 64K not-null <codeph>Bit</codeph> columns,

32 <codeph>Text8[255]</codeph> columns, 100 <codeph>Text8[80]</codeph> columns,

or 32 <codeph>LongText8</codeph> columns. </p>

<p>Each table can have up to 32 indexes. Index keys can contain any number

of key columns, but the total size of the key must not exceed 248 bytes for

unique indexes, and 244 bytes for non-unique indexes.</p>

<p>The number of rows in a table is practically limited by available resources.</p>

<p>The maximum size of a transaction is limited by available memory.</p>

<section id="GUID-02B71501-420B-4CAA-B2D0-7490BBD5432E"><title>See also</title> <p><xref href="GUID-47419CFB-163D-5A4E-8A00-C73773353BDF.dita">Column

type characteristics</xref> and <xref href="GUID-785B2F0B-E7E6-5DAE-98F1-6C32BED25964.dita">Database

storage overhead</xref>.</p> </section>

</conbody></concept>