if null mysql

Solutions on MaxInterview for if null mysql by the best coders in the world

showing results for - "if null mysql"
Caterina
12 Jul 2017
1SELECT * 
2FROM table 
3WHERE YourColumn IS NOT NULL;
Idriss
01 Jul 2019
1SELECT *
2FROM contacts
3WHERE last_name IS NULL;
Melina
15 Nov 2016
1IFNULL(MAX(EMAIL), "example@google.com") as email
Olivia
09 Jan 2021
1 SELECT 
2    contactname, IFNULL(bizphone, homephone) phone
3FROM
4    contacts;
Jarrod
20 Apr 2020
1SELECT * from TABLE where CODE IS NULL OR CODE!='C'
Liesl
08 Apr 2018
1SELECT IFNULL(NULL, "W3Schools.com");
queries leading to this page
mysq not nullinclude null values in mysqlphp mysql function is not null in the argumentuse where if value not null mysqlmysql return 1 if column is not nullcheck if column is not null mysqlmysql query where is nullmysql if value is null returnif condition in mysql null checkwhere field is not null mysqltoad for mysql values 28 null mysql is null or equal nullfind not null from mysqlis null in where mysqlif is not null mysqlmysql 3d null vs is nullmysql case when is not nullmysql as value return nullmysql select column if not nullhow to get null values in mysqlif 28null 29set 0 or string if the return rows is empty in mysqlhow to use is not null in mysqlmysql field null checkmysql if field is nullhow to set not null in mysqlhow set not null in mysqlmysql if check is nullmysql not null checkmysql select column value if not nullmysql where field is not nullselect all null values mysqlmysql how to select where not nullifnull in sqllaravel where not nullmysql not null in where clausesetting null in mysqlmysql check if variable is null or empty if conditionmysql check null in selectmysql select where is nullmysql empty sql resultmysql logical if column exists column nullablenot null in mysql databasemysql not equal nullmysql null value selecthow does is null work in mysqlif not null in mysqlmysql why are null usedwhere clause in mysql for not nullmysql include null valuesmysql 21 3d nullnot null where condition in mysqlcheck if cell is empty mysqlhow to check null column in mysqlvalue of null in mysqlhow to use null in mysqlmysql null if not foundmysql set value if nullin not null mysqlmysql nullsnot null in mysql where clausesql null value query phpmyadminset null value mysql qyerymysql how to check for null valuemysql where clause or nullif null sql statementphp mysql select where column is nullfind values is null in mysqlmysql records became nullmysql or is nullin null in mysqlmysql if column is nullmysql where and nullis not null mydqlmysql null checkboxmysql select without nullc 23 mysql if value nullsql check if a field is empty stringfunction empty mysqlcolumn is empty string mysqlmysql not null 5chow to check null value in if condition in mysqlmasql not nullhow to do null in mysqljava check if null mysqlcheck if column is empty mysqlmysql empty fieldmysql if null then nullmysql check for null valuesmysql null not inmysql if is nullmysql nullablemake a value null in mysqlmysql use default value when setting nullif null query in mysqlmysql check if a column not nullhow to handle search query in mysql which is nullif null then 0 in mysqlmysql if value is false checkvalue null is null in mysqlmysql is null or emptyhow to check if anything is null in a database mysqlmysql search for null valuescheck if null variable mysqlmysql query not null 22 22show the column with null value mysqlmysql is not nullsql check if column is null or emptysql check if a field is emptynull if mysql ormysql how to find something with null valuemysql check if a column is nullhow to check null values in mysql queryifnull 28 27 27 2c 27 27 29 3d 27 27mysql nullif vs ifnullimport mysql with null valuesnull if mysqlmysql get values that are not nullmysql check if variable is not null or emptyhow to find null value in mysqlsql check field emptychecking for null values in mysqlspecify null mysqlmysql 3a where 3d nullhow to check for the null in mysql mysql table using select queryif isnull mysqldont show null values mysqlmysql if dr read nullmysql if isnull then 0not null is mysqlmysql where in query is nullmysql row where column is nullmysql select where nullhow to check if string is empty phpmyadminand where is null mysqlmysql if column is null show something elseget null value in mysqlmysql where value not nullselect without null value row in mysqlin not null musqlmysql in is nullcheck column is null mysqlif i tick null in mysqlmysql query get where coumn 3d nullmysql select null as valuecheck for default and blank in mysql not null mysqlmysql where clause for nullcheck if not null in mysqlmysql date nullhow to make value null in mysqlreturn something if null mysqlmysql check is null in querymysql and is not nullmysql query where in return nullmysql where column equal to value or nullmysql not null valuesmysql and column nullhow to check when a table field is blank in if statementhow to select the value if one columns is not null in mysql querymysql if 0 or nullmysql how to set a nullmysql not null and not emptymysql check 3d nullmysql check if string is valorizedmysql either null or valuecheck null value mysqlmysql is not null not workingmysql query select null valuesmysql select if nullmysql check for null or emptymysql ifnull then nullifnullnot null mysql queryif null en mysqlmysql select where is null 3bis null mysqlhow to search an empty value in a row in sqlmaysql is nullnull mysql querymysql set default nullmysql select if column values is nullmysql if null or empty then 0myql where not nullmysql if is null thenis null query in mysqlmysql handle null valuesmysql is nullcheck if the column value is not null mysqlmysql find all empty columnsand is not null mysqlfilter empty string mysqlfind null values in mysqlcolum is null mysqlselect rows where column value is null mysqlmyslq ifnullmysq set nullfinding null in a column mysqlif compare value is not null where mysqlmysql if not null column is nullnull not null mysqlnot null check mysqlmysql update column if value is nullmysql whene is not nullmysql not null or emptymysql where not nullmysql where any value not nullmysql nullc ountcheck null column in where clause in mysqlmysql null querymy sql not isnullnot equal mysql not check nullsql if cell contains blankmysql string is empty or nullusing 27or 27 with 27null 27 in mysqlmysql condition to check not nullnot equal to null in mysqlmysql is null 3d 0jsp check if mysql query is nullmysql if sis nullmysql default value if nullselect value where not null mysqlmysql if else nullmysql if not null functionupdate mysql set if not nullif null then zero in mysqlmysql where equals nullifnull sqlif null like mysqlmysql if value is nullhow to check if an column is null in msqlset to null mysqlupdate mysql where nullnot null seklect mysqlmysql where not empty or nullmysql select where field is empty trimmysql is null 5dget not null values in mysqlmysql can i use null valuecheck if colmun null mysqlmysql if not null or emptycheck if colum is null in mysqlif not null sqlmysql inc 3bude null valuesif null mysql queriesmysql where is null not workingmysql 22nulls 22mysql if null elsewhat generates a null value in mysqlcheck is null mysqlif not null in mysql queryif null mysqlmysql query on nullmysql check not nullmysql not null meanignmysql null conditionis empty in mysqlhow to check blank column and set null in pythonmysql check if value nullmysql string not empty or nullmysql check is not null integer queryhow to use not null in mysqlmysql condition where value is null or 1mysql check if value is empty or nullmysql where column is nullis not null and empty in mysqlmysql set nullget null data using where status in 28null 2c 27value 27 29 query mysqllinux php mysql if column is not null or not emptyhow to get data where null mysqlcheck if null in mysqlcheck column value is null or empty in sqlhow to get empty column in sqlmysql function nullmssql check if value is nullquery where null mysqlmysql if 0 then nullmysql use default value when using nullmysql is null testmysql how specify a null valueselect column with null values in mysqlmysql select if null then 0not null mysqlif null in mysqlmysql is null and emptysearch where row is null in mysqlmysql and varchar nullmysql string field null or emptymysql check if value is nullmysql trigger check if column value is nullmysql checek is nullmysql set default when nullmysql like if nullcheck field where null mysqlmysql not null querymysql if null then 0if or null mysqlis null function in mysqlcheck if is null mysqlmysql isnotnullmysql set value for nullwhere null value in mysqlmysql if value is null then statementmysql select null if not existsmysql check if not nullget one record is not null in items in mysqlhow to select null values in mysqlhow to search null value in mysqland condition with is not null mysqlmysql null wheremysql when is not nullhow to get null value with where condition in mysqlmysql check is something is not nullmysql apply nullnot null mysqlmysql detect if is 22 22set nullnull value in mysql querymysql check not null or emptymysql sql not nullhow to make database can accepts a null values in mysqlhow to return null in mysqlselect where column value is null mysqlmysql if not exists return nullmysql if a column is null return 0 else 1is not null in mysqlmysql to check if value is nullselect where not null mysqlhwo to check is null in mysqlhow to put check in on column mysql is null using if elsemysql is not null whereif no value then mysqlin in mysql with nullmysql null checkmysql 21 3d 3d nullmysql select where value is nullmysql null by defaultupdate where value 3d null mysqlmysql error when nullmysql select like or is nullmysql 27if 27 in 27select 27 statement if nullsql query to find if entry is null or emptyset a value to null in mysqlusing if null in mysqlcheck null value in mysqlmysql where 3d nullwhat is meant by null value in mysqlget null records for mysqlmysql 21 3d and nullmysql is null in selectmysql cannto be nullmysql query for not nullnull value mysqlvalue 21 3d null mysql queryand not null mysqlselect null value in mysqlmysql where field is nullmysql and not nullnulls in mysqlmysql check if cell is nullmysql not nullmysal field always nullcheck if column varchar is not empty mysqlmysql check if field is null or emptymysql if null in selectmysql if statement null checkmysql is null checkmysql if nullget null values from mysqlalasql is not nullnull and not null mysql diffretnmysql query where column is nullcheck if null mysqlhow to get value saved in mysql database when the field is set as nullsyntax for not null in mysqmysql null ifhow to use if check null in field in mysqlis not null mysqlmysql null or empty my sql check if value is nullmysql select where 3d nullaccording to condition make column value null in mysql querymysql in nullmysql if emptymysql null 3d nullmysql when not nullmysql query if null then 0mysql is not null or emptynot selecting null in mysqlset data null in mysqlmysql field not nullmysql null valuesmysql how to select null valuemysql check if colum is nullmysql 8 0 if null not workinghow to get null value records in mysqlmysql if is not nullfind null in mysqlmysql select null value mysql query where nullmysql check if column is empty on select statementmysql check if nullif is null mysql selecthow to get null field only in mysql recordshow to check to null in mysqlmysql where is not null or emptyis null operator in mysqlmysql check for nullmysql select ifnullis null check in mysqlifnull in mysqlupdate query in sql not null mysqlcheck empty field mysqlsql how to check if something is nullmysql if column value is null thenmysql is emptymysql if blank then nullmy sql where value nullif not null statement in mysqlmysql if statement check nullif null and if in mysqlin null mysqlmysql value isnt nullmysql select the condition if not nullmysql 3d 3d nullmysql select return default if nullwhere field 3d null mysqlcheck not null in mysqlif mysqlu query result 3d 3d nullmysql 0 and null in where clausemysql query syntax null or is not nullwhere id 3dnull mysqlselect not null in mysqlmysql is null statementmysql if null thenisnull 281 29 in mysqlifnull 28 29 functionphp mysql function is not null as argumentnot null check in mysql querymysql or nullmysql conditional statements with nullwhere not null mysqlmysql check empty string or nullif condition in mysql query to check not nullwhere column is not nu 3b 3b mysqlnull if in mysqlmysql where in nullnull value in mysqlwhere not in mysql null return nothingmysql ignore where if nullmysql is nullselect query in mysql is nullquery null values in mysqlmysql ifnull function usagemysql where null 5cmysql ifnullmysql sql null checkmysql check blank or nullnot in null mysqlhow to check for null values in mysqlphp mysql get where nullselect with where field not null mysqlhow to check null in mysqlmysql select if nullmysql trigger check if value is nullmysqlnoy is nullmysql check null value in wherewhere column is not null mysqlsql if not null mysqlmysql query any value that is notsql check if variable is nullquery to set default value null in mysqlmysql select where column is nullmysql 3d nullset is null mysqlmysql is null thenselect null values in mysqlmysql select if value is not nullupdate where data is null in mysqlhow to check in value in mysql is not nullwhere is null mysql 5chow to check if a value is null in mysqlmysql set null valueselect where null mysqlwhere key 21 3d null mysqlshow not null and is null mysql records mysql get where nullmysql 60 is emptymysql set null value querymysql sql select isnull or emptysql check if fields are emptywhat does not null and null in mysqlhow to write null in mysqlmysql check if value not nullmysql check null or emptymysql check empty or nullmysql 0 if nullmysql if value then select null or notmysql select all where value is nullmysql set column value null if emptyif null in mysq 3bmysql select where clause column pass 22is not null 22 functionmysql if null selectnull in mysql where clausemysql no nullis not null soqlmysql is not null on selectchecking null in mysqlset default null mysqlmysql check for not null 3dnull in mysqlmysql select value or nullmysql field is nullcheck not null mysqlcheck null mysqlmysql query check if nullmysql update if where clause is not nullmysql select default value if nullif null condition in mysqlmysql where null conditionget raw from mysql where condition or is nullmysql is null doesnt workmysql check if row is nullcheck if something is not nullsintaxe if null mysqlif user has nothing in a colomn mysqlmysql return null if not existsselect mysql column not nullmysql where any value but not nulllinux php mysql select where column is not nullmysql does not equal nullmysql query is nullhow do i know if mysql table column is nullif 21 3d null in mysql queryhow to check null value in mysqlmysql where null or emptycheck a value is null mysqlmysql null 21 3d 1mysql char default nullselect where is null mysqlhow to check if variable is null in mysqlwhere clause not null in mysqlifnotnull mysqlmysql field null or emptycheck if variable is null mysqlmysql find null valuesmysql 22in 22 query return nullmysql select if not nullmysql if null then another columnmysql query null value mysql where if nullif null in mysql querymysql where not is nullis not null not working in mysqlhow to seelct null and is null mysqlmysql notnullmysql not null whymysql select if is nullmysql set null where valuemysql if null then false else 1mysql where empty stringmysql and filed not nullmysql query nullmysql if null or emo 3dpty checkquery for not null in mysqldoes results next work if colomn is null mysqlpython 2b check database column null or emptymysql having null valuecheck if null and if blank in mysqlwhat meaning of not null my mysqlmysql where something or nullhow to find null values in mysqlif table column is blank then my sql 5ccheck null in mysqlmysql is null check 0select from where is not null mysqlmysql test is not nullwhere not null mysql querymysql how to check if column is null or not emptyget field null query mysqlcheck empty value in mysqlmysql is null or valuewhere check null mysqlpick the null value from mysqlupdate mysql where is nullmysql nullifmysql is null where clausemysql set default value if nullmysql notis nullmysql if value not nullhow to check if field is empty in sql 3d null mysqlmysql check if any columns is null is null in mysql mysql where isn 27t nullmysql when is nullmysql put i if not nullmysql query is not nulland where not null mysqlif null or empty mysqlselect not null values in mysqlget null values in mysqlhandle null value in mysqlhow to set string null in mysqlselect not null mysqlcheck is null in mysqlnull value not insert in mysqlmysql if column is null thenmysql check if null or emptymysql not null check 28 27 27 29return default if null mysqlmysql check if is nullmysql where not null or emptymysql in null 2c 0null check mysqlmysql routines if column value is null thenmy sql is not nullmysql check on not nullhandle empty columns sqlquery if field is null mysqlcheck if value is null mysql 5 7how to check if any column is null in sqlmysql check default null valuemy sql see null resulthow to not serlect null values in mysql get null column value of mysqlwrite mysql query where nullmysql where valu 3d not nulljava check if sql field emptymysql is not empty or nullhow to check if a column value is null mysql c 23mysql having is not nullselect bases of null field in mysqlmysql does not null mean no nullhow to specify emty cell in sqlcheck for not null in mysqlcheck is not null mysqlnot null en mysqlis null condition not working in mysqlprint column which has null value in mysqlhow to check not null in mysql querymysql does null 3d 0mysql check variable is not nullhow does 27or 27 work in mysql with nullsql check for empty fieldmysql test if null mysql where null examplemysql value different or nullmysql if select is not nullhow to a value from null 4 mysqlcheck not null in mysql queryif ifnull mysqlmysql is non nullmysql select where clause column pass 22is not null 22check if value from mysql is nullget null data using where in 28null 29 query mysqlmysql select null valuesnot null in mysqlmysql select only null valuesmysql value nullmysql query if null then stringif not null mysql selectmysql if select is nullmysql check if null or empty stringis null in mysqlmysql is empty or nullmysql a 3dnullmysql update if column is nullmysql null valueif not null condition in mysqlmake mysq value nullselect is not null mysqlmysql nullmysql query where in nullmysql null check in selectis null or 0 mysqlmysql if has column valu then where clause condition or null valuemysql ifnull not nullget the condition where data comes null in mysql querydefine a null value mysqlnull check in mysql querymysql select not null valuemysql if a query is nullmysql check if variable is null or emptywhere column 3d null mysqlmysql update if column is null if existsmysql prevent nullmysql check if column can be null c 23 how to check if sql table column is nullhow to handle null in mysqlif statement in mysql select column is value not nullmysql meaning 3a 3d nullfind columns with null values mysqlset null in mysqlif value is null set mysql query to default nullcheck column is not null in mysqlmysqlis not nullmysql query wher ecolumn is not nullcheck null in mysql querynot is null mysqlmysql set null default valuemysql errors are nullif and ifnull mysqlif null mysql exampleis not null in mysql querymysql if not null in where clausemysql check that value is not nullnull mysqlhow to find mysql returned a null valuemysql default value if null where incheck value not null in mysql querymysql if is not nullsql ifnullmysql where id 21 3d nullcommand mysql not nullis null on mysqlmysql null value in clasusemysql query not nullmysql value if nullfind empty cell in sql servermysql select values that are not nullmysql is null or emptyhow to check for empty column in sqlnot null while mysqlhow to create mysql variable with null valuescheck if value is null sqlconcaet mysql nullcheck if empty cell sqlvalue not null mysqlmysql select if is null thennot null function in mysqlnot null mysql meaninglike ifnullmysql null or valuemysql if equal to nullif is null en mysqlmysql st to nullmysql set value to nullmysql where value or nullmysql procedure if null valuemysql not is null 3c 3d 3e null mysqlhow to check null in msqlsql for empty fielddefault not null mysqlif null select mysqlcheck if field is empty sqlmysql where a value isnt nullmysql control null check if column is null or empty in sqlhandle empty column sqlmysql null not showing on queryis 22 22 equivalent to null in mysqlmysql is null equals nullcheck for null mysqlmysql null vs not nullmysql set to nullmysql return null valueswhat does where null do in mysqlnot null in mysql selectmysql where not nullget not null value in mysqlcheck null in where in query mysqlmysql where values is nullmysql check is nullmysql select if field is nullmysql where column 3d nullwhat is not null in mysqlmysql dont include nullmysql not null meaningmysql where if else is not nullmysql check if record is not nulselect from where not null in mysqlnot null query in mysqlmysql if null inserempty condition in mysqlmysql value is not null or emptymysql check nullmake value null mysqlselect ifnull sqlmysql if condition not nullmysql attribut not nullmysql if nullis null mysqlcreate null value mysqlmysql check if null in selectmysql is null 3d nullmysqk where not nullif null then 0 mysqlmysql using where with nullnon null mysqlwhere is not null mysqlcount if column is null mysqlwhy null is considered and number in mysqlwhen not null mysqlmysql default nullmssql select if null then default valuemysql5 null ifmysql text not nullmysql check if column is emptymy sql query when is nullmysql check not null and emptymysql column check if null or emptysearch for null values in mysqlhow to find the null value in mysqlnot null mysql queryquery to find null values in mysqlmysql variable 0 if nullcheck for null in mysql caseisnull isnotnull mysqlmysql does not set nullmy sql check null valuesis not null condition in mysqlmysql set as nullmysql equals nullmysql select nuulmysql function return value if nullif null or empty mysql wheremysql select null or defaultmysql sql isnotnulnot show null mysqlmysql not null whereif column equal null mysqlmysql is not null in where clausemysql empty collumwhere column null mysqlcheck if query equals nullwhere clause null in mysqlmysql isemptymysql check if a field is null mysql if null examplemysql null check in where clausemysql value if not nullupdate column if is null mysqlif sub select null default value mysqlisnull mysqlmysql null value checkdefault value null mysql querymysql check on nullhow to check that field is null or not in sqlhow to check if not null in mysqlmy sql not nullnot null condition in mysqlmysql where and not nullhow to check not null in mysqlrdbms quesry wif value is null the printmysql how to check null valuemysql if not null in selectmysql check if column is nullwhere not null in mysqlempty value in mysqlcheck attribute of empty table sqlhow to pass null value in mysql querymysql test nullmysql null no yesis not nul mysqlmysql condition in update null with if empty stringmysql where field 3d nullmysql check column is not nullif statement to check if variable is null in mysql proceduresql query to check if column is null or emptymysql isnull 3d nullselect if null mysqlmysql meaning 22 3a 3d 22 nullif value is null set mysql query to as defined nullcheck if not nullmysql check if column is not null or emptymysql if not nullcheck if value is null mysqlset default value null in mysqlselect query with not null in mysqlmysql select nullmysql if null or emptymysql select not nullmysql where is nullselect statement in ifnull condition mysqlwhere is null mysqlwhere int is not null mysqlmysql where nullcheck if column is null mysqlmysql not exists or is nullvalue is not null mysql querymysql if null tghensql check if column empty within a selectmysql is null columnmysql if null querymysql if null inside wheremysql if null where inif empty mysqlcheck on column 21 3d null in my sql mysql query to check null valuecheck if mysql query returns no valuemysql check if field is nullmysql select default valuemysql where is not nullfill blanks with null in mysqlcheck is null with and and or in mysql check if not null mysqlmysql if not null then 1check column is empty epfhow to set null value in mysqlset null mysql querymysql o and null in where clausemysql if value is null return other columnnot equal to null or empty in mysqlmysql if empty then nullhow to return 0 if null in mysqlmysql if not null or empty in selectmysql show null in empty fields in query resultmysql don return value if nullwhat will mysql return if value is null0 if null mysqlwhere null in mysqlhow to use mysql not null on many attributeselect where cell is blank mysqlnull in mysqlmysql query check not nullmysql id nullmysql select not equal nullmysql check where not in with null columnmysql column is nullmysql check if null or 0mysql if value is null return 0how to check for null in mysql scriptifnull mysqlhow to assign null value in mysqlwhat is mysql ifnullif statement return null mysqlhow to put check in on column mysql is null or notnull check in mysqlnot null check in mysqlmysql where is not or nullmysql query to select all empty fieldsmysql where like nullmysql check if not null or emptymysql value 21 3d nullhow to express nil in mysqlmysql if null 0select if not null mysqlnot null in mysql select querywhere column is empty sqlmysql get null recordsif not null mysqlmysql select where column is not nullmysql min value only if something else is not nullmysql contains nullcheck value is null or not in mysqlsql field is emptymysql check if null in where clausequery is not null mysqlmysql is null or 3d nullif equal null mysqlis null in mysql serverreturn all if where condition is null mysqlhow to check if a column is not null in mysqlmysql if is null or emptymysql query select if not nullselect column if null show my value in mysqlcheck if variable is null in mysqlif statement in mysql select column is nullmysql null if emptyverifying if a field is nullis not ull mysqlwhat is null in mysqlis in not null mysqlwhen to use null and not null in mysqlif coloum in database is blankmysql string is not empty or nullhow to check is null in mysqlmysql check is not nullmy sql where nullmysql null in where clausecheck is null in select statement mysqlmysql check where not nullmysql if null or not nullmysql string null not nullselect where value is null mysqlsql wuery to check if value is null or emptymysql check if is not nullmysql s not nullvariable null check in mysqlif is null mysqlmysql where column is not nullfield is null mysqlhow to fill default value if column is null in mysqlcheck if a field is empty sqlfind mysql nullsis null in where clause mysqlis null in my sqlmysql when string is nullcheck if value not null mysqlif nullmysql why is null and not 3d nullmysql select where not nullmysql where value is nullmysql not null check sqlif null 0 mysqlmysql where equal to nullmysql and field not nullsqlsever if column is null what is null value in mysqlhow t set null vallue in dataabase using mysqlselect is null mysqlmysql check if variable is nulldefault null in mysqlcheck for null value in mysqlif mysql not nullmysql query fir not nullmysql value is not nullmysql table field not nullwhy data is null in mysqlhow to select whwre not null in mysqlmysql add column default nullmysql select where not nuollhow to check for null value in mysqlor null mysqlmysql only get null valuesmy sql where not nullfind individual null values from each column in mysqlmysql default null or 22 22mysql null 2fnullmy sql is nullinser null value mysqlcheck if a column is null in mysqlwhere null mysqlhow to get null field only in mysql records with in conditionsql string column is emptymysql are null consided equal 3fwhere value is empty mysqlselect default value when null mysqlis not null en mysqlset null mysqlif not equal to null mysqlnull vs not null mysqlvalidate null mysqlmysql column null show my valuequery to check null values in mysqlnot is null msyqlis null in mysqlif function with null mysql if null mysql