To force case-sensitivity, you can use the BINARY keyword, as in WHERE prod_name REGEXP BINARY 'product. Matches Are Not Case-Sensitive Regular expression matching in MySQL are not case-sensitive either case will be matched. So can REGEXP be used to match entire column values (so that it functions like LIKE)? Actually, yes, using the ^ and $ anchors, as will be explained later in this tutorial. SQL will enforce that the letter and number are at the two ends of the string because there is no pattern or literal character before or after our match set. This will match any letter followed by anything, followed by a number. REGEXP, on the other hand, looks for matches within column values, and so if the text to be matched existed in the middle of a column value, REGEXP would find it and the row would be returned. For your needs use: WHERE ColumnName LIKE ' a-z 0-9'. If the text to be matched existed in the middle of a column value, LIKE would not find it and the row would not be returned (unless wildcard characters were used). Like operator is used to apply / filter using wildcards on mysql results as below - Regexp provides support of full regular expression filtration of results. Last names contain B followed by R or U SELECT * from customers where last_name REGEXP 'b'Īs we can see we should get letters ' b' followed by ru simply meaning br and bu as b is common here the search pattern of REGEXP searched this way and fetch the information.If you were to try them both you'd discover that the first returns no data and the second returns one row. With the caret ^, we have queried the names which letters start with ' my' and contain ' se'. Something it won’t do with REGEXP (), even if with an at the beginning of the regex. Last names starting with MY or contain SE SELECT * from customers where last_name REGEXP '^my|se' And the second is that MySQL does some sensible optimizations when LIKE is used, in particular it narrows down the number of rows with the index, when possible. Using $ we have fetched the last name ending with letters ey and on using this we can query out the pattern matching the ending of a string. This may also have implications on Performance. EF.Functions.Like however gets translated into string LIKE pattern ESCAPE escapeChar. Contains gets translated into (CHARINDEX(pattern, string) > 0) OR pattern ''. Last names end with EY or ON SELECT * from customers where last_name REGEXP 'ey$|on$' StartsWith gets translated as (string LIKE pattern + '' AND CHARINDEX(pattern, string) 1) OR pattern '' where.
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