MYSQL BOOLEAN HOW TO
In this tutorial, you have learned how to perform MySQL Boolean full-text searches with many useful Boolean operators.
The 50% threshold means if a word appears in more than 50% of the rows, MySQL will ignore it in the search result. The MySQL full-text search capability provides a simple way to implement various search techniques (natural language search, query expansion search, and boolean search) into your application running MySQL. In addition, the following leading plus or minus with wildcard are invalid: +*, +. MySQL will report an error if you search word is ‘mysql+’ or ‘mysql-‘. It only supports leading plus or minus sign. InnoDB full-text search does not support trailing plus (+) or minus (-) sign. It ignores other operators and uses the operator that is closest to the search word, for example, ‘+-mysql’ will become ‘-mysql’. MySQL does not support multiple Boolean operators on a search query on InnoDB tables e.g., ‘++mysql’. Notice that MyISAM tables do not require this, although the search is quite slow. To perform Boolean queries, InnoDB tables require all columns of the MATCH expression has a FULLTEXT index. MySQL does not automatically sort rows by relevance in descending order in Boolean full-text search. ‘my*’ MySQL boolean full-text search main features 
The 0 and 1 represent the integer values. If you want to use Boolean literals, use true or false that always evaluates to 0 and 1 value. MySQL considered value zero as false and non-zero value as true. mysql> create table BooleanDemo -> ( -> IsOn BOOLEAN -> ) Query OK, 0 rows affected (0.58 sec) Now check internal structure of the above table. They provide a TINYINT data type instead of Boolean or Bool data types. The BOOLEAN and BOOL are equivalents of TINYINT (1), since they are synonyms.
To find rows that contain words starting with “my” such as “mysql”, “mydatabase”, etc., you use the following: MySQL does not contain built-in Boolean or Bool data type. The following table illustrates the full-text search Boolean operators and their meanings: Operator WHERE MATCH(productName) AGAINST( 'Truck -Pickup' IN BOOLEAN MODE ) Code language: SQL (Structured Query Language) ( sql ) MySQL Boolean full-text search operators
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