![]() Table took just under 31 minutes to populate, versus 25 for the ordinaryįTS3 and FTS4 are nearly identical. Hardware configuration used to perform the SELECT queries above, the FTS3 The FTS3 table consumes around 2006 MB onĭisk compared to just 1453 MB for the ordinary table. Selects only those rows that contain "linux" as a discrete token. Or "EnterpriseLinux" (as it happens, the Enron E-Mail Dataset does notĪctually contain any such terms), whereas the MATCH query on the FTS3 table The LIKE query matches rows that contain terms such as "linuxophobe" Of course, the two queries above are not entirely equivalent. SELECT count(*) FROM enrondata2 WHERE content LIKE '%linux%' /* 22.5 seconds */ SELECT count(*) FROM enrondata1 WHERE content MATCH 'linux' /* 0.03 seconds */ Is inserted into both an FTS table and an ordinary SQLite table One or more words (hereafter "tokens"), even if the tableįor example, if each of the 517430 documents in the The full-text indexĪllows the user to efficiently query the database for all rows that contain The FTS3 and FTS4 extension modules allows users to create special tables with aīuilt-in full-text index (hereafter "FTS tables"). Portions of the original FTS3 code were contributed to the SQLite projectĭeveloped and maintained as part of SQLite. Issues with these older modules and their use should be avoided. This article describes the deployment and usage of FTS3 and FTS4.įTS1 and FTS2 are obsolete full-text search modules for SQLite. Matches those terms considering the operators and groupings the user has Phrase, and the full-text query system finds the set of documents that best Of terms, perhaps connected by a binary operator or grouped together into a With documents placed on the World Wide Web". Way to describe full-text searches is "what Google, Yahoo, and Bing do If you have a phone number column in the format 5556667777, but you want the format (555) 666-7777, you can format it using the SUBSTR() function.FTS3 and FTS4 are SQLite virtual table modules that allows users to performįull-text searches on a set of documents. Z (optional can be omitted) represents the number of characters in the resulting string. Y represents the starting position to obtain the substring (the first character position in the string is always 1). ![]() X represents the string you want to obtain a substring from. Obtains a substring of the string you’re working with ![]() SUBSTR("column name",'start_position','end_position') If the character appears multiple times in the string, the function returns the position of its first occurrence. Y represents the character whose position you want to obtain. X represents the string that contains the character whose position you want to obtain. Z represents the character or string that is used to replace Y.įinds the position of a character in a string Y represents the character or substring you want to replace. X represents the string that contains the character or string you want to replace. Replaces a character or substring in your string with another character or string REPLACE("column name", 'replace_this', 'with_this') Returns the number of characters in the string LOWER(X)Ĭonverts the string to all lowercase letters UPPER(X)Ĭonverts the string to all uppercase letters REPLACE(X, Y, Z) There are many core functions that you can use for strings and numeric values, but here are some of the common ones you can use for strings: LENGTH(X) Atlassian Analytics uses SQLite to power the non-query Visual SQL steps. ![]()
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