Note that the SQL equals operator ( =) cannot be used to check for the null value-you have to use is null instead. SQL: COUNT(CASE WHEN A IS NOT NULL AND A != '' THEN 1 END) The following expression counts the rows that have neither the null value or the empty string. For that, SQL makes a distinction between empty strings and the null value. The function counta can be implemented with a case expression as well. SQL: COUNT(CASE WHEN A = 42 AND B = 43 THEN 1 END) The function Countifs can often be implemented with an and condition in the case expression. SQL: COUNT(CASE WHEN A = 42 THEN 1 END) + DISTINCT COUNT () will return a row for each unique count. SELECT COUNT (DISTINCT programname) AS Count, programtype AS Type FROM cmproduction WHERE pushnumberpushnumber GROUP BY programtype. SQL: COUNT(CASE WHEN A LIKE 'Marvin%' THEN 1 END)Ĭountif over multiple columns is done as the sum of one count function per column: Excel: =COUNTIF( Ax: Cy, 42) Count all the DISTINCT program names by program type and push number. The like operator uses underscore ( _) as a wildcard for a single character and the percent sign ( %) as the wildcard for any number of characters-like ? and * in Excels countif. To use wildcards in SQL, you have to use the like operator. Unlike the Excel countif function, SQL does not apply wildcard matches when comparing strings with the equals sign ( =). PostgreSQL, the Oracle database and SQLite do-per default-take case differences into account. Even the default varies between database products: MySQL, MariaDB and SQL Server perform case-insensitive comparisons by default. Whether or not SQL text comparisons ignore case differences depends on the so-called collation. SQL: COUNT(CASE WHEN A = 'Marvin' THEN 1 END) Text values, however, must be put under single quotes 0: Excel: =COUNTIF( Ax:Ay, "Marvin") The condition is not put under quotes-not even when using a comparison operator: Excel: =COUNTIF(Ax:Ay, "> 42") The column is explicitly used in the that is put into the case expression. The the group by and over clauses specify the rows. In SQL, the picking the rows is separate from the picking of the columns. In Excel, the defines arbitrary cells-Ax:Ay in the following examples. The same behavior can be obtained in SQL by using a case expression inside the count function: SQL: COUNT(CASE WHEN THEN 1 END) The Microsoft Excel function countif counts cells that satisfy a condition: Excel: =COUNTIF(, )
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