For what it is worth, Sybase (related to SQL Server) will tolerate both single and double quotes in sql queries. You need to be consistent, though.

I am using Sybase ASE 12.0 and DBD::Sybase to allow users to query a full-text server that joins with another database.

I put my queries into variables and escape any embedded quotes. This permits me to employ nested quotes in certain situations:

$query = "select col_a, col_b, col_c from tablea, tableb 
where tablea..pkey = tableb..fkey
and tablea..column_x = '$fts'";
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The $fts string must be enclosed in single quotes, and may contain literals, which need to be enclosed in double quotes:

$fts = "(seedling \<or\> kernel \<or\> embryo) \<and\> \"viab*\" ";
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Note that the only time I actually need to escape the quotes are when a double quote is employed within a string variable.

The final form of the query passed to the Sybase server is:

select a,b,c from tablea, tableb
where tablea..pkey = tableb..fkey
and tablea..column_x = '(kernel <or> embryo) <and> "viab*"'

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