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                                                                    EXHIBIT 31.1


                    CERTIFICATION OF CHIEF EXECUTIVE OFFICER
            PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002

      I, Gaurav S. Dhillon, certify that:

1.    I have reviewed this annual report on Form 10-K of Informatica
      Corporation;

2.    Based on my knowledge, this annual report does not contain any untrue
      statement of a material fact or omit to state a material fact necessary to
      make the statements made, in light of the circumstances under which such
      statements were made, not misleading with respect to the period covered by
      this annual report;

3.    Based on my knowledge, the financial statements, and other financial
      information included in this annual report, fairly present in all material
      respects the financial condition, results of operations and cash flows of
      the registrant as of, and for, the periods presented in this annual
      report;

4.    The registrant's other certifying officer and I are responsible for
      establishing and maintaining disclosure controls and procedures (as
      defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant
      and we have:

            a.    Designed such disclosure controls and procedures, or caused
                  such disclosure controls to be designed under our supervision,
                  to ensure that material information relating to the
                  registrant, including its consolidated subsidiaries, is made
                  known to us by others within those entities, particularly
                  during the period in which this annual report is being
                  prepared;

            b.    Evaluated the effectiveness of the registrant's disclosure
                  controls and procedures and presented in this annual report
                  our conclusions about the effectiveness of the disclosure
                  controls and procedures, as of the end of the period covered
                  by this annual report based on such evaluation; and

            c.    Disclosed in this annual report any change in the registrant's
                  internal control over financial reporting that occurred during
                  the registrant's most recent fiscal quarter (the registrant's
                  fourth fiscal quarter in the case of an annual report) that
                  has materially affected, or is reasonably likely to materially
                  affect, the registrant's internal control over financial
                  reporting; and

5.    The registrant's other certifying officer and I have disclosed, based on
      our most recent evaluation of internal control over financial reporting
      to the registrant's auditors and the audit committee of registrant's board
      of directors (or persons performing the equivalent functions):

            a.    All significant deficiencies and material weaknesses in the
                  design or operation of internal control over financial
                  reporting which are reasonably likely to adversely affect the
                  registrant's ability to record, process, summarize and report
                  financial information; and

            b.    Any fraud, whether or not material, that involves management
                  or other employees who have a significant role in the
                  registrant's internal control over financial reporting.


                                                 /s/ GAURAV S. DHILLON
                                       -------------------------------------
                                                   Gaurav S. Dhillon
                                       Chief Executive Officer and President

Dated: March 10, 2004