Take the first 20 text characters and compute and store the CRC32 or MD5 of that value. That value acts as a signature. You can then find all distinct signatures, or all rows with duplicate signatures for further analysis You could event try building a signature on the full text string.
From: "Shmagi Kavtaradze" <kavtaradze.s@gmail.com> To: pgsql-novice@postgresql.org Sent: Friday, November 20, 2015 2:21:36 AM Subject: [NOVICE] Combine Top-k with similarity search extensions
I am performing similarity check over a column in a table with about 3500 entries. Column is populated with text data from text file. Performing a check results in 3500 * 3500 rows and it takes forever to calculate for my virtual machine. Is there any way to calculate for top-k results, to decrease amount and time needed? What I mean is that, for example when checking two sentences, if first several words does not match, to stop checking that sentences and move on.