MySQL SELECT not finding known values - mysql

Question

There is probably something simple here that I'm just not seeing, but I've been trying all I can think of for a few hours. It's time to toss it to more knowledgable folks...
I want to attempt to intercept a duplicate index, so my auto increment value doesn't advance. Plus, after this much time, it has just become one of those things I have to solve at this point.
Starting with an empty table, I call the procedure with PricingHeaderID_In set to zero in order to invoke the INSERT logic.
Lookup1 obviously finds nothing, because there is nothing to find, and pricingHeaderID1 is NULL. Then, the new row is inserted, Lookup2 retrieves the newly inserted row as expected, and pricingHeaderID2 shows the correct value.
Now, I call the procedure with EXACTLY the same values everywhere, Lookup1 still finds nothing, and pricingHeaderID1 is NULL. That causes the insert logic to run, and MySQL correctly detects a duplicate.
My question is simple: If MySQL can detect that the values will cause a duplicate key, then why is Lookup1 failing?
Here's my table definition:
CREATE TABLE PricingHeaders (
PricingHeaderID bigint NOT NULL AUTO_INCREMENT,
UserID bigint NOT NULL,
ClientName varchar(100) NOT NULL,
Subdivision varchar(100) NOT NULL,
SubjectProperty varchar(100) NOT NULL,
DatePrepared date NOT NULL,
MonthsSearched smallint DEFAULT NULL,
Bedrooms tinyint DEFAULT NULL,
Bathrooms tinyint DEFAULT NULL,
Stories tinyint DEFAULT NULL,
SquareFeet smallint DEFAULT NULL,
YearBuilt smallint DEFAULT NULL,
HasPool bit DEFAULT 0,
Created datetime DEFAULT CURRENT_TIMESTAMP,
Modified datetime DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
PRIMARY KEY (PricingHeaderID),
UNIQUE KEY UserClientPropertyDate (UserID,ClientName,SubjectProperty,DatePrepared),
INDEX UserSubdivision (UserID,Subdivision)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE utf8_general_ci;
And here's my stored procedure:
CREATE PROCEDURE SavePricingHeader ( Token_In VARCHAR(36),
PricingHeaderID_In bigint,
UserID_In bigint,
ClientName_In varchar(100),
Subdivision_In varchar(100),
SubjectProperty_In varchar(100),
DatePrepared_In date,
MonthsSearched_In smallint,
Bedrooms_In tinyint,
Bathrooms_In tinyint,
Stories_In tinyint,
SquareFeet_In smallint,
YearBuilt_In smallint,
HasPool_In bit )
BEGIN
DECLARE errNo int DEFAULT 0;
DECLARE errMsg varchar(250) DEFAULT 'OK';
DECLARE currOp varchar(250) DEFAULT 'Init';
DECLARE pricingHeaderID1 bigint DEFAULT NULL;
DECLARE pricingHeaderID2 bigint DEFAULT NULL;
DECLARE tokenValidated bit DEFAULT 0;
DECLARE sqlErrNo CHAR(5) DEFAULT '00000';
DECLARE sqlErrMsg TEXT DEFAULT '';
DECLARE CONTINUE HANDLER FOR SQLEXCEPTION
BEGIN
GET DIAGNOSTICS CONDITION 1 sqlErrNo = RETURNED_SQLSTATE, sqlErrMsg = MESSAGE_TEXT;
SET errNo = 1;
SET errMsg = 'SQL Error';
END;
IF errNo = 0 THEN
SET currOp = 'Extend session';
CALL ExtendSession(Token_In, tokenValidated);
END IF;
IF errNo = 0 THEN
IF tokenValidated = 0 THEN
SET errNo = 9001;
SET errMsg = 'Invalid session.';
END IF;
END IF;
IF errNo = 0 THEN
SET currOp = 'Lookup1';
SELECT `PricingHeaderID` INTO pricingHeaderID1 FROM `PricingHeaders`
WHERE `UserID` = UserID_In
AND `ClientName` = ClientName_In
AND `SubjectProperty` = SubjectProperty_In
AND `DatePrepared` = DatePrepared_In;
IF errNo = 0 THEN
IF pricingHeaderID1 IS NOT NULL THEN
IF pricingHeaderID1 <> PricingHeaderID_In THEN
SET errNo = 9002;
SET errMsg = 'Duplicate Index.';
END IF;
END IF;
END IF;
END IF;
IF errNo = 0 THEN
IF PricingHeaderID_In = 0 THEN
SET currOp = 'Insert';
INSERT INTO `PricingHeaders` (
`UserID`,
`ClientName`,
`Subdivision`,
`SubjectProperty`,
`DatePrepared`,
`MonthsSearched`,
`Bedrooms`,
`Bathrooms`,
`Stories`,
`SquareFeet`,
`YearBuilt`,
`HasPool`
) VALUES (
UserID_In,
ClientName_In,
Subdivision_In,
SubjectProperty_In,
DatePrepared_In,
MonthsSearched_In,
Bedrooms_In,
Bathrooms_In,
Stories_In,
SquareFeet_In,
YearBuilt_In,
HasPool_In
);
IF errNo = 0 THEN
SET pricingHeaderID1 = LAST_INSERT_ID();
END IF;
ELSE
SET currOp = 'Update';
SET pricingHeaderID1 = PricingHeaderID_In;
UPDATE `PricingHeaders` SET
`ClientName` = ClientName_In,
`Subdivision` = Subdivision_In,
`SubjectProperty` = SubjectProperty_In,
`DatePrepared` = DatePrepared_In,
`MonthsSearched` = MonthsSearched_In,
`Bedrooms` = Bedrooms_In,
`Bathrooms` = Bathrooms_In,
`Stories` = Stories_In,
`SquareFeet` = SquareFeet_In,
`YearBuilt` = YearBuilt_In,
`HasPool` = HasPool_In
WHERE `PricingHeaderID` = PricingHeaderID_In;
END IF;
END IF;
IF errNo = 0 THEN
SET currOp = 'Lookup2';
SELECT `PricingHeaderID` INTO pricingHeaderID2 FROM `PricingHeaders`
WHERE `UserID` = UserID_In
AND `ClientName` = ClientName_In
AND `SubjectProperty` = SubjectProperty_In
AND `DatePrepared` = DatePrepared_In;
END IF;
IF errNo = 0 THEN
IF pricingHeaderID2 IS NULL THEN
SET errNo = 9003;
SET errMsg = 'Not retrieved.';
END IF;
END IF;
SELECT pricingHeaderID1, pricingHeaderID2, errNo, errMsg, currOp, sqlErrNo, sqlErrMsg;
END

Answer 1

Your basic problem is your call to the second procedure,
which must look like
CALL ExtendSession(Token_In, #tokenValidated)
Whe4n you want to retrieve an OUT variable in MySQL#
CREATE TABLE PricingHeaders (
PricingHeaderID bigint NOT NULL AUTO_INCREMENT,
UserID bigint NOT NULL,
ClientName varchar(100) NOT NULL,
Subdivision varchar(100) NOT NULL,
SubjectProperty varchar(100) NOT NULL,
DatePrepared date NOT NULL,
MonthsSearched smallint DEFAULT NULL,
Bedrooms tinyint DEFAULT NULL,
Bathrooms tinyint DEFAULT NULL,
Stories tinyint DEFAULT NULL,
SquareFeet smallint DEFAULT NULL,
YearBuilt smallint DEFAULT NULL,
HasPool bit DEFAULT 0,
Created datetime DEFAULT CURRENT_TIMESTAMP,
Modified datetime DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
PRIMARY KEY (PricingHeaderID),
UNIQUE KEY UserClientPropertyDate (UserID,ClientName,SubjectProperty,DatePrepared),
INDEX UserSubdivision (UserID,Subdivision)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE utf8_general_ci;
CREATE PROCEDURE ExtendSession(IN Token_In VARCHAR(36), OUT tokenValidated int)
BEGIN
SET tokenValidated = 1;
END;
✓
CREATE PROCEDURE SavePricingHeader ( Token_In VARCHAR(36),
PricingHeaderID_In bigint,
UserID_In bigint,
ClientName_In varchar(100),
Subdivision_In varchar(100),
SubjectProperty_In varchar(100),
DatePrepared_In date,
MonthsSearched_In smallint,
Bedrooms_In tinyint,
Bathrooms_In tinyint,
Stories_In tinyint,
SquareFeet_In smallint,
YearBuilt_In smallint,
HasPool_In bit )
BEGIN
DECLARE errNo int DEFAULT 0;
DECLARE errMsg varchar(250) DEFAULT 'OK';
DECLARE currOp varchar(250) DEFAULT 'Init';
DECLARE pricingHeaderID1 bigint DEFAULT NULL;
DECLARE pricingHeaderID2 bigint DEFAULT NULL;
DECLARE tokenValidated bit DEFAULT 0;
DECLARE sqlErrNo CHAR(5) DEFAULT '00000';
DECLARE sqlErrMsg TEXT DEFAULT '';
DECLARE CONTINUE HANDLER FOR SQLEXCEPTION
BEGIN
GET DIAGNOSTICS CONDITION 1 sqlErrNo = RETURNED_SQLSTATE, sqlErrMsg = MESSAGE_TEXT;
SET errNo = 1;
SET errMsg = 'SQL Error';
END;
IF errNo = 0 THEN
SET currOp = 'Extend session';
CALL ExtendSession(Token_In, #tokenValidated);
END IF;
IF errNo = 0 THEN
IF #tokenValidated = 0 THEN
SET errNo = 9001;
SET errMsg = 'Invalid session.';
END IF;
END IF;
IF errNo = 0 THEN
SET currOp = 'Lookup1';
SELECT `PricingHeaderID` INTO pricingHeaderID1 FROM `PricingHeaders`
WHERE `UserID` = UserID_In
AND `ClientName` = ClientName_In
AND `SubjectProperty` = SubjectProperty_In
AND `DatePrepared` = DatePrepared_In;
IF errNo = 0 THEN
IF pricingHeaderID1 IS NOT NULL THEN
IF pricingHeaderID1 <> PricingHeaderID_In THEN
SET errNo = 9002;
SET errMsg = 'Duplicate Index.';
END IF;
END IF;
END IF;
END IF;
IF errNo = 0 THEN
IF PricingHeaderID_In = 0 THEN
SET currOp = 'Insert';
INSERT INTO `PricingHeaders` (
`UserID`,
`ClientName`,
`Subdivision`,
`SubjectProperty`,
`DatePrepared`,
`MonthsSearched`,
`Bedrooms`,
`Bathrooms`,
`Stories`,
`SquareFeet`,
`YearBuilt`,
`HasPool`
) VALUES (
UserID_In,
ClientName_In,
Subdivision_In,
SubjectProperty_In,
DatePrepared_In,
MonthsSearched_In,
Bedrooms_In,
Bathrooms_In,
Stories_In,
SquareFeet_In,
YearBuilt_In,
HasPool_In
);
IF errNo = 0 THEN
SET pricingHeaderID1 = LAST_INSERT_ID();
END IF;
ELSE
SET currOp = 'Update';
SET pricingHeaderID1 = PricingHeaderID_In;
UPDATE `PricingHeaders` SET
`ClientName` = ClientName_In,
`Subdivision` = Subdivision_In,
`SubjectProperty` = SubjectProperty_In,
`DatePrepared` = DatePrepared_In,
`MonthsSearched` = MonthsSearched_In,
`Bedrooms` = Bedrooms_In,
`Bathrooms` = Bathrooms_In,
`Stories` = Stories_In,
`SquareFeet` = SquareFeet_In,
`YearBuilt` = YearBuilt_In,
`HasPool` = HasPool_In
WHERE `PricingHeaderID` = PricingHeaderID_In;
END IF;
END IF;
IF errNo = 0 THEN
SET currOp = 'Lookup2';
SELECT `PricingHeaderID` INTO pricingHeaderID2 FROM `PricingHeaders`
WHERE `UserID` = UserID_In
AND `ClientName` = ClientName_In
AND `SubjectProperty` = SubjectProperty_In
AND `DatePrepared` = DatePrepared_In;
END IF;
IF errNo = 0 THEN
IF pricingHeaderID2 IS NULL THEN
SET errNo = 9003;
SET errMsg = 'Not retrieved.';
END IF;
END IF;
SELECT pricingHeaderID1, pricingHeaderID2, errNo, errMsg, currOp, sqlErrNo, sqlErrMsg;
END
✓
CALL SavePricingHeader(1,0,1,'test','subd','subepro',NOW(), 1,2,1,1,12,1981,0)
pricingHeaderID1 | pricingHeaderID2 | errNo | errMsg | currOp | sqlErrNo | sqlErrMsg
---------------: | ---------------: | ----: | :----- | :------ | :------- | :--------
1 | 1 | 0 | OK | Lookup2 | 00000 |
✓
db<>fiddle here