![]() ![]() In this case, % is referred to as a "wildcard." In the type of SQL that Mode uses, LIKE is case-sensitive, meaning that the above query will only capture matches that start with a capital "S" and lower-case "noop. ANY or SOME or ALL: If ALL is specified then ilike returns true if str matches all patterns, otherwise returns true if it matches at least one pattern. The % used above represents any character or set of characters. You can prepend NOT keyword to negate the result return by LIKE condition. In general, putting double quotes around a word or phrase will indicate that you are referring to that column name. LIKE performs a case-sensitive match and ILIKE performs a case-insensitive match. The double quotes (as opposed to single: ') are a way of indicating that you are referring to the column name "group", not the SQL function. ![]() Note: "group" appears in quotations above because GROUP is actually the name of a function in SQL. What can PostgreSQL do to speed up those operations and what can be done in general to first understand the problem and secondly to achieve better. People use those things all over the place in their application and therefore it makes sense to approach the topic from a performance point of view. These index types are not equally efficient, so it makes sense to dig into the subject matter and figure out what is best when. the 'like' expression is different in that is uses pattern matching to find the correct values, and as such requires a bit more work in the back end. LIKE and ILIKE are two fundamental SQL features. Run the code to see which results are returned. Both index type can handle LIKE as well as ILIKE. In this example, the results from the Billboard Music Charts dataset will include rows for which "group" starts with "Snoop" and is followed by any number and selection of characters. LIKE is a logical operator in SQL that allows you to match on similar values rather than exact ones. Starting here? This lesson is part of a full-length tutorial in using SQL for Data Analysis. ![]()
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