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ROW_COUNT()

This function used return the number of rows updated, inserted, or deleted by the preceding statement and -1 when no rows affected.

Syntax:
INSERT INTO [table_name] ([field1,field2,…]) VALUES ([val,val2,..]);
SELECT ROW_COUNT();

Example:

INSERT INTO wordlist (keyword,docid) VALUES (’sample1′,123), (’sample2′,124), (’sample3′,125);
SELECT ROW_COUNT();

ON DUPLICATE KEY UPDATE

If inserted row cause a duplicate value in a UNIQUE index or PRIMARY KEY,Then It updated using ON DUPLICATE KEY .

Syntax:
INSERT INTO [table_name] ([field1,field2,…]) VALUES ([val1,val2,..]) ON DUPLICATE KEY UPDATE [val1,val2,..].

Example:

INSERT INTO wordlist (keyword,docid) VALUES (’sample’,3435) ON DUPLICATE KEY UPDATE docid=docid+1

chr

chr
- It return a specific character for a given ASCII Value

Synatx:

string chr ( int ascii)

It returns a one-character string containing the character specified

by ascii.

Example:

$str = chr(65);
echo $str

It returns ‘A’.